TOEFL чтение тест №3

Directions

In this section, you will read three passages and answer reading comprehension questions about each passage. Most questions are worth one point, but the last question in each set is worth more than one point. The directions indicate how many points you may receive.
You have 60 minutes to read all of the passages and answer the questions. Some passages include a word or phrase followed by an asterisk (*). Go to the bottom of the page to see a definition or an explanation of these words or phrases.

Questions 1-12

Two Atomic Clocks

The nucleus of a radioactive atom disintegrates spontaneously and forms an atom of a different element while emitting radiation in the process. The original atom is called the parent isotope* and its stable product is called the daughter or progeny isotope. For example, rubidium-87 decays by emitting an electron from its nucleus to form a stable daughter called strontium-87. Because the rate of nuclear decay is constant regardless of temperature and pressure conditions, radioactive decay provides a dependable way of keeping time. Radioactive isotopes alter from one type of atom to another at a fixed rate from the moment they are created anywhere in the universe. Since we can calculate the decay rate and also count the number of newly formed progeny atoms and the remaining parent atoms, we can use the ratio as a kind of clock to measure the age of minerals and other materials.
The rate at which a radioactive element decays is known as the half-life of the element. This is the time necessary for one-half of the original number of radioactive atoms in a sample to decay into a daughter product. After two half-lives, the number of atoms remaining after the first half-life will have decayed by half again. Thus, the number of remaining parent atoms is reduced geometrically over time. With some elements, the half-life is very long. Rubidium-87, for example, has a half-life that has been estimated at nearly 48.8 billion years, much longer than the current estimated age of the universe. With other elements, this period can be as short as a few days or even minutes. If we know the half-life of a decaying element, it is possible to calculate the ratio of parent to stable progeny that will remain after any given period of time.
Geologists use a sensitive instrument called a mass spectrometer to detect tiny quantities of the isotopes of the parent and progeny atoms. By measuring the ratio of these, they can calculate the age of the rock in which the rubidium originally crystallized. Because the number of progeny is growing as the parent is decaying and this is occurring at a constant rate, after one-half life the ratio is one parent to one progeny. After two half-lives the ratio is 1 to 3.
Rubtdium-87 has often been used to date rocks since it is a widespread element. Various elements including rubidium are incorporated into minerals as they crystallize from magma* or metamorphic rock. During this process the rubidium is separated from any strontium progeny that existed before the rock formed and so we know that the measurable alteration from parent to progeny can be dated from this point. As the radioactive decay of rubidium-87 begins, new progeny atoms of strontium-87 start to accumulate in the rock. In the dating of rocks using these elements, it is important that the rock sample has not been altered subsequent to its formation by other geologic processes or contamination of any kind. Rocks as old as 4.6 billion years can be dated with some degree of reliability using this method.
Another radioactive element useful for dating is carbon-14, which decays into nitrogen-14. With a half-life of 5,730 years, carbon-14 decays much more rapidly than rubidium-87 and so is useful for measuring the ages of objects from the recent historical and geologic past, such as fossils, bones, wood, and other organic materials. Whereas rubidium-87 is incorporated into rocks during their formation, carbon-14, which is an essential element of the cells of organisms, becomes incorporated into living tissues as organisms grow. The ratio of carbon-14 to stable carbon isotopes in the organism is the same as it is in the atmosphere. When a living organism dies, no more carbon dioxide is absorbed and so no new carbon isotopes are added. The daughter nitrogen-14 isotope, existing in gaseous form, leaks out of the dead organism, and thus, we cannot use it to compare the ratio of original to daughter as is done with rubidium-87 and its daughter. However, as the amount of carbon-14 in the dead organism becomes less over time, we can compare the proportion of this isotope remaining with the proportion that is in the atmosphere and from this calculate the approximate number of years since the organism has died. Dating dead organic material by this method is moderately reliable in samples up to about 50,000 years old, but beyond that the accuracy becomes unreliable.

*isotope: one of the differing forms of an atomic element
*magma: material that is in liquid form and which cools on the Earth's surface to form rock

1. The word "alter" in the passage is closest in meaning to adapt change revise vary

The nucleus of a radioactive atom disintegrates spontaneously and forms an atom of a different element while emitting radiation in the process. The original atom is called the parent isotope and its stable product is called the daughter or progeny isotope. For example, rubidium-87 decays by emitting an electron from its nucleus to form a stable daughter called strontium-87. Because the rate of nuclear decay is constant regardless of temperature and pressure conditions, radioactive decay provides a dependable way of keeping time. Radioactive isotopes alter from one type of atom to another at a fixed rate from the moment they are created anywhere in the universe. Since we can calculate the decay rate and also count the number of newly formed progeny atoms and the remaining parent atoms, we can use the ratio as a kind of clock to measure the age of minerals and other materials.

2. The rate of nuclear decay in rubidium-87 is always the same changes over time depends on temperature depends on temperature and pressure

[Refer to the full passage.]

3. The word "This" in the passage refers to element half-life rate time

The rate at which a radioactive element decays is known as the half-life of the element. This is the time necessary for one-half of the original number of radioactive atoms in a sample to decay into a daughter product. After two half-lives, the number of atoms remaining after the first half-life will have decayed by half again. Thus, the number of remaining parent atoms is reduced geometrically over time. With some elements, the half-life is very long. Rubidium-87, for example, has a half-life that has been estimated at nearly 48.8 billion years, much longer than the current estimated age of the universe. With other elements, this period can be as short as a few days or even minutes. If we know the half-life of a decaying element, it is possible to calculate the ratio of parent to stable progeny that will remain after any given period of time.

4. The half-life of an element is a reliable way of measuring sample size is a measure of decay rate in radioactive elements is considered an unreliable way of calculating age is approximately half the age of the atoms it contains

[Refer to the full passage.]

5. What can be inferred about the reliability of using radioactive atoms to calculate ages of rock samples? The reliability increases over time. The reliability decreases with older samples. The reliability of the parent atom is greater than the progeny. The reliability of the progeny atom is greater than the parent.

[Refer to the full passage.]

6. According to the passage, from what point can we measure the ages of rocks? From the point at which rubidium-87 became part of the rock structure From the point at which strontium-87 started to decay From the point at which the rocks rubidium-87 and strontium-87 joined From the point at which later contamination entered the rock samples

[Refer to the full passage.]

7. The word "essential" in the passage is closest in meaning to redundant stable dependable vital

Another radioactive element useful for dating is carbon-14, which decays into nitrogen-14. With a half-life of 5,730 years, carbon-14 decays much more rapidly than rubidium-87 and so is useful for measuring the ages of objects from the recent historical and geologic past, such as fossils, bones, wood, and other organic materials. Whereas rubidium-87 is incorporated into rocks during their formation, carbon-14, which is an essential element of the cells of organisms, becomes incorporated into living tissues as organisms grow. The ratio of carbon-14 to stable carbon isotopes in the organism is the same as it is in the atmosphere. When a living organism dies, no more carbon dioxide is absorbed and so no new carbon isotopes are added. The daughter nitrogen-14 isotope, existing in gaseous form, leaks out of the dead organism, and thus, we cannot use it to compare the ratio of original to daughter as is done with rubidium-87 and its daughter. However, as the amount of carbon-14 in the dead organism becomes less over time, we can compare the proportion of this isotope remaining with the proportion that is in the atmosphere and from this calculate the approximate number of years since the organism has died. Dating dead organic material by this method is moderately reliable in samples up to about 50,000 years old, but beyond that the accuracy becomes unreliable.

8. According to paragraph 5, what happens to an organism after it dies? It tends to deteriorate rapidly. The various carbon isotopes decay. The supply of carbon-14 is no longer replenished. The stable carbon isotopes deteriorate. Paragraph 5 is marked with an arrow ->

-> Another radioactive element useful for dating is carbon-14, which decays into nitrogen-14. With a half-life of 5,730 years, carbon-14 decays much more rapidly than rubidium-87 and so is useful for measuring the ages of objects from the recent historical and geologic past, such as fossils, bones, wood, and other organic materials. Whereas rubidium-87 is incorporated into rocks during their formation, carbon-14, which is an essential element of the cells of organisms, becomes incorporated into living tissues as organisms grow. The ratio of carbon-14 to stable carbon isotopes in the organism is the same as it is in the atmosphere. When a living organism dies, no more carbon dioxide is absorbed and so no new carbon isotopes are added. The daughter nitrogen-14 isotope, existing in gaseous form, leaks out of the dead organism, and thus, we cannot use it to compare the ratio of original to daughter as is done with rubidium-87 and its daughter. However, as the amount of carbon-14 in the dead organism becomes less over time, we can compare the proportion of this isotope remaining with the proportion that is in the atmosphere and from this calculate the approximate number of years since the organism has died. Dating dead organic material by this method is moderately reliable in samples up to about 50,000 years old, but beyond that the accuracy becomes unreliable.

9. According to paragraph 5, why can't scientists compare the ratio of carbon-14 to nitrogen-14? The amount of nitrogen-14 is not predictable. The ratio of these two elements doesn't change. Nitrogen-14 has an unpredictable decay rate. Carbon-14 tends to evaporate too quickly. Paragraph 5 is marked with an arrow [->]

-> Another radioactive element useful for dating is carbon-14, which decays into nitrogen-14. With a half-life of 5,730 years, carbon-14 decays much more rapidly than rubidium-87 and so is useful for measuring the ages of objects from the recent historical and geologic past, such as fossils, bones, wood, and other organic materials. Whereas rubidium-87 is incorporated into rocks during their formation, carbon-14, which is an essential element of the cells of organisms, becomes incorporated into living tissues as organisms grow. The ratio of carbon-14 to stable carbon isotopes in the organism is the same as it is in the atmosphere. When a living organism dies, no more carbon dioxide is absorbed and so no new carbon isotopes are added. The daughter nitrogen-14 isotope, existing in gaseous form, leaks out of the dead organism, and thus, we cannot use it to compare the ratio of original to daughter as is done with rubidium-87 and its daughter. However, as the amount of carbon-14 in the dead organism becomes less over time, we can compare the proportion of this isotope remaining with the proportion that is in the atmosphere and from this calculate the approximate number of years since the organism has died. Dating dead organic material by this method is moderately reliable in samples up to about 50,000 years old, but beyond that the accuracy becomes unreliable.

10. According to paragraph 5, the amount of carbon-14 in an organism replaces other carbon isotopes after an organism dies tends to be the same as the other carbon isotopes increases rapidly when an organism dies deteriorates from the moment of death Paragraph 5 is marked with an arrow [->].

-> Another radioactive element useful for dating is carbon-14, which decays into nitrogen-14. With a half-life of 5,730 years, carbon-14 decays much more rapidly than rubidium-87 and so is useful for measuring the ages of objects from the recent historical and geologic past, such as fossils, bones, wood, and other organic materials. Whereas rubidium-87 is incorporated into rocks during their formation, carbon-14, which is an essential element of the cells of organisms, becomes incorporated into living tissues as organisms grow. The ratio of carbon-14 to stable | carbon isotopes in the organism is the same as it is in the atmosphere. When a living organism dies, no more carbon dioxide is absorbed and so no new carbon isotopes are added. The daughter nitrogen-14 isotope, existing in gaseous form, leaks out of the dead organism, and thus, we cannot use it to compare the ratio of original to daughter as is done with rubidium-87 and its daughter. However, as the amount of carbon-14 in the dead organism becomes less over time, we can compare the proportion of this isotope remaining with the proportion that is in the atmosphere and from this calculate the approximate number of years since the organism has died. Dating dead organic material by this method is moderately reliable in samples up to about 50,000 years old, but beyond that the accuracy becomes unreliable.

11. Look at the four squares [?] that indicate where the following sentence could be added to the passage. Both the unstable carbon-14 and stable carbon isotopes are taken in from the carbon dioxide present in the atmosphere. Where would the sentence best fit? Choose the letter of the square that shows where the sentence should be added. A B C D

Another radioactive element useful for dating is carbon-14, which decays into nitrogen-14. [A] With a half-life of 5,730 years, carbon-14 decays much more rapidly than rubidium-87 and so is useful for measuring the ages of objects from the recent historical and geologic past, such as fossils, bones, wood, and other organic materials. Whereas rubidium-87 is incorporated into rocks during their formation, carbon-14, which is an essential element of the cells of organisms, becomes incorporated into living tissues as organisms grow. [B] The ratio of carbon-14 to stable carbon isotopes in the organism is the same as it is in the atmosphere. [C] When a living organism dies, no more carbon dioxide is absorbed and so no new carbon isotopes are added. [D] The daughter nitrogen-14 isotope, existing in gaseous form, leaks out of the dead organism, and thus, we cannot use it to compare the ratio of original to daughter as is done with rubidium-87 and its daughter. However, as the amount of carbon-14 in the dead organism becomes less over time, we can compare the proportion of this isotope remaining with the proportion that is in the atmosphere and from this calculate the approximate number of years since the organism has died. Dating dead organic material by this method is moderately reliable in samples up to about 50,000 years old, but beyond that the accuracy becomes unreliable.

12. Directions: Select the appropriate phrases from the answer choices and match the dating technique to which they relate. TWO of the answer choices will NOT be used. This question is worth 4 points. Write the letters of the answer choices in the spaces where they belong. Refer to the full passage.
Answer Choices A) Can be used for dating artifacts made of bones or wood B) Destroys progeny isotopes C) Essential to living organisms D) Has a half-life of billions of years E) Incorporated into minerals when they crystallized F) Progeny cannot be used for dating G) Unreliable for dating samples H) Used for dating dead trees I) Used for dating rocks	Rubidium-87 * * * Carbon-14 * * * *

Questions 13-25

Demographic Transition

Historically, as countries have developed industrially, they have undergone declines in death rates followed by declines in birth rates. Over time they have tended to move from rapid increases in population to slower increases, then to zero growth and finally to population decreases. The model which demographers use to help explain these changes in population growth is known as the demographic transition model. In order to properly appreciate the demographic transition model, it is necessary to understand two basic concepts: the crude* birth rate (CBR) and the crude death rate (CDR). The CBR is determined by taking the number of births in a country in a given year and dividing it by the total population of the country and then multiplying the answer by one thousand. So, for example, the CBR of the United States in 2004 was 14 (in other words, there were 14 births per thousand living people in that year). CDR is worked out in a similar way. The CDR for the United States in 2004 was 8 per thousand.
The first stage of the demographic transition model portrays a preindustrial era when both the birth rate and the death rate were high. Typically, women gave birth to a large number of babies. This was partly due to cultural and religious pressures but also because families required a large number of children, since often many didn't survive into adulthood due to the harsh living conditions. Furthermore, children were needed to help adults work the land or perform other chores. The death rate was high due to the high incidence of diseases and famine and also because of poor hygiene. Total population tended to fluctuate due to occasional epidemics, but overall there was only a very gradual long-term increase during this stage.
During the second stage, improvements in hygiene, medical care, and food production led to a decrease in the death rate in newly industrializing regions of Western Europe. However, birth rates remained high due to tradition and because many people were involved in agrarian occupations. The combination of a lowered CDR and a stable CBR led to dramatic increases in population starting at the beginning of the nineteenth century.
In stage three, birth rates also began to fall. In cities there was less incentive to produce large numbers of children, since city dwellers no longer worked the land, and the cost of raising children in an urban environment was greater than in rural districts. Furthermore, more children survived into adulthood due to improved living conditions. These economic pressures led to a lower CBR and over time the numbers of people being born started to approximate the numbers dying.
The final stage, which some demographers have called the postindustrial stage, occurs when birth rates and death rates are about equal. In this case there is zero natural population growth. Over time the birth rate may fall below the death rate, and without immigration the total population may slowly decrease. By the early twenty-first century, several European countries were experiencing population declines due to the CDR outstripping the CBR. For example, in Italy in 2004 there were about 9 births per thousand against 10 deaths per thousand.
The demographic transition took about 200 years to complete in Europe. Many developing countries are still in stage two of the demographic transition model: births far outstrip deaths. In these countries, CDR has declined due to improvements in sanitation and increases in food productivity, but the birth rate has still not adjusted downward to the new realities of improved living conditions. This imbalance of births over deaths in the developing world is the fundamental reason for the dramatic population explosion in the latter half of the twentieth century. However, population statistics indicate that in many less developed countries the CBRs have begun to decline over recent decades, giving rise to optimism in some quarters about future trends. The rapid industrialization of many parts of the developing world has meant that these countries have reached stage three of the model much faster than countries in the developed world did during the nineteenth century. This fact has led many demographers to predict that world population will reach an equilibrium level sooner and at a lower total than more pessimistic earlier predictions.

*crude: not analyzed into specific classes

13. The word "it" in the passage refers to population year country number

Historically, as countries have developed industrially, they have undergone declines in death rates followed by declines in birth rates. Over time they have tended to move from rapid increases in population to slower increases, then to zero growth and finally to population decreases. The model which demographers use to help explain these changes in population growth is known as the demographic transition model. In order to properly appreciate the demographic transition model, it is necessary to understand two basic concepts: the crude birth rate (CBR) and the crude death rate (CDR). The CBR is determined by taking the number of births in a country in a given year and dividing it by the total population of the country and then multiplying the answer by one thousand. So, for example, the CBR of the United States in 2004 was 14 (in other words there were 14 births per thousand living people in that year). CDR is worked out in a similar way. The CDR for the United States in 2004 was 8 per thousand.

14. According to paragraph 1, what is useful about the demographic transition model? It helps explain trends in population growth over time. It can be used to measure birth and death rates. It clarifies the causes of population increase. It predicts the relative speed of population patterns. Paragraph 1 is marked with an arrow [->].

-> Historically, as countries have developed industrially, they have undergone declines in death rates followed by declines in birth rates. Over time they have tended to move from rapid increases in population to slower increases, then to zero growth and finally to population decreases. The model which demographers use to help explain these changes in population growth is known as the demographic transition model. In order to properly appreciate the demographic transition model, it is necessary to understand two basic concepts: the crude birth rate (CBR) and the crude death rate (CDR). The CBR is determined by taking the number of births in a country in a given year and dividing it by the total population of the country and then multiplying the answer by one thousand. So, for example, the CBR of the United States in 2004 was 14 (in other words there were 14 births per thousand living people in that year). CDR is worked out in a similar way. The CDR for the United States in 2004 was 8 per thousand.

15. The word "portrays" in the passage is closest in meaning to suggests represents transmits associates

The first stage of the demographic transition model portrays a preindustrial era when both the birth rate and the death rate were high. Typically, women gave birth to a large number of babies. This was partly due to cultural and religious pressures but also because families required a large number of children, since often many didn't survive into adulthood due to the harsh living conditions. Furthermore, children were needed to help adults work the land or perform other chores. The death rate was high due to the high incidence of diseases and famine and also because of poor hygiene. Total population tended to fluctuate due to occasional epidemics, but overall there was only a very gradual long-term increase during this stage.

16. In paragraph 2, which of the following is NOT mentioned as relevant to the high birth rates in the preindustrial stage? The high level of childhood deaths The need for help in work situations The pressures of tradition The high rate of maternal deaths Paragraph 2 is marked with an arrow [->].

-> The first stage of the demographic transition model portrays a preindustrial era when both the birth rate and the death rate were high. Typically, women gave birth to a large number of babies. This was partly due to cultural and religious pressures but also because families required a large number of children, since often many didn't survive into adulthood due to the harsh living conditions. Furthermore, children were needed to help adults work the land or perform other chores. The death rate was high due to the high incidence of diseases and famine and also because of poor hygiene. Total population tended to fluctuate due to occasional epidemics, but overall there was only a very gradual long-term increase during this stage.

17. What can be inferred from paragraph 2 about the effect of epidemic diseases on population during the preindustrial stage? They tended to dramatically lower the population growth. They caused the population to decline temporarily. They reduced overall population significantly. They led to sudden overall increases in the birth rate. Paragraph 2 is marked with an arrow [->]

-> The first stage of the demographic transition model portrays a preindustrial era when both the birth rate and the death rate were high. Typically, women gave birth to a large number of babies. This was partly due to cultural and religious pressures but also because families required a large number of children, since often many didn't survive into adulthood due to the harsh living conditions. Furthermore, children were needed to help adults work the land or perform other chores. The death rate was high due to the high incidence of diseases and famine and also because of poor hygiene. Total population tended to fluctuate due to occasional epidemics, but overall there was only a very gradual long-term increase during this stage.

18. The word "agrarian" in the passage is closest in meaning to basic menial farming village

During the second stage, improvements in hygiene, medical care, and food production led to a decrease in the death rate in newly industrializing regions of Western Europe. However, birth rates remained high due to tradition and because many people were involved in agrarian occupations. The combination of a lowered CDR and a stable CBR led to dramatic increases in population starting at the beginning of the nineteenth century.

19. According to paragraph 4, what was one of the main causes of the drop in birth rates? The improvements in hygiene The lack of agricultural work The development of urbanization The superior environment Paragraph 4 is marked with an arrow [->].

-> In stage three, birth rates also began to fall. In cities there was less incentive to produce large numbers of children, since city dwellers no longer worked the land, and the cost of raising children in an urban environment was greater than in rural districts. Furthermore, more children survived into adulthood due to improved living conditions. These economic pressures led to a lower CBR and over time the numbers of people being born started to approximate the numbers dying.

20. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information. The population gradually declines when there is no immigration and deaths exceed births. In time there may be an overall drop in population as the birth rate and death rate fluctuate. The relationship between birth and death rates is an important reason for limiting immigration. If population losses aren't replaced through immigration, the birth rate may fall below the death rate.

The final stage, which some demographers have called the postindustrial stage, occurs when birth rates and death rates are about equal. In this case there is zero natural population growth. Over time, the birth rate may fall below the death rate, and without immigration the total population may slowly decrease. By the early twenty-first century. several European countries were experiencing population declines due to the CDR outstripping the CBR. For example, in Italy in 2004 there were about 9 births per thousand against 10 deaths per thousand.

21. The word "equilibrium" in the passage is closest in meaning to economic stable variable fixed

The demographic transition took about 200 years to complete in Europe. Many developing countries are still in stage two of the demographic transition model: births far outstrip deaths. In these countries, CDR has declined due to improvements in sanitation and increases in food productivity, but, the birth rate has still not adjusted downward to the new realities of improved living conditions. This imbalance of births over deaths in the developing world is the fundamental reason for the dramatic population explosion in the latter half of the twentieth century. However. population statistics indicate that in many less developed countries the CBRs have begun to decline over recent decades, giving rise to optimism in some quarters about future trends. The rapid industrialization of many parts of the developing world has meant that these countries have reached stage three of the model much faster than countries in the developed world did during the nineteenth century. This fact has led many demographers to predict that world population will reach an equilibrium level sooner and at a lower total than more pessimistic earlier predictions.

22. According to paragraph 6, what is at the root of the huge population increases during the twentieth century? The improvements in health throughout the developing world The fact that birth rates are increasing in many countries The lack of resources in many developing countries The failure of the CDR to respond to economic pressures Paragraph 6 is marked with an arrow [->].

-> The demographic transition took about 200 years to complete in Europe. Many developing countries are still in stage two of the demographic transition model: births far outstrip deaths. In these countries, CDR has declined due to improvements in sanitation and increases in food productivity, but the birth rate has still not adjusted downward to the new realities of improved living conditions. This imbalance of births over deaths in the developing world is the fundamental reason for the dramatic population explosion in the latter half of the twentieth century. However, population statistics indicate that in many less developed countries the CBRs have begun to decline over recent decades, giving rise to optimism in some quarters about future trends. The rapid industrialization of many parts of the developing world has meant that these countries have reached stage three of the model much faster than countries in the developed world did during the nineteenth century. This fact has led many demographers to predict that world population will reach an equilibrium level sooner and at a lower total than more pessimistic earlier predictions.

23. Why does the author mention the optimism felt in some quarters about future population trends? To introduce the fact that birth rates in some developing countries may be declining faster than anticipated To emphasize that most researchers have taken a pessimistic view of population expansion To show that the demographic transition is a valid model of population trends To suggest that some countries have worked hard at reducing birth rates

[Refer to the full passage.]

24. Look at the four squares [?] that indicate where the following sentence could be added to the passage. Industrialization had led to increased urbanization. Where would the sentence best fit? Choose the letter of the square that shows where the sentence should be added. A B C D

In stage three, birth rates also began to fall. [A] In cities there was less incentive to produce large numbers of children, since city dwellers no longer worked the land, and the cost of raising children in an urban environment was greater than in rural districts. [B] Furthermore, more children survived into adulthood due to improved living conditions. [C] These economic pressures led to a lower CBR and over time the numbers of people being born started to approximate the numbers dying. [D]

25. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points. Write the letters of the answer choices in the spaces where they belong. Refer to the full passage. The demographic transition model links trends in population growth to the level of industrial development. * * * Answer Choices A) Preindustrial populations tended to increase due to the large numbers of births and a slowly declining death rate. B) Due to economic pressures, the birth rate dropped to match the death rate, leading to zero growth and eventually a decline in population. C) High birth and death rates are associated with a preindustrial stage of development when there was only a gradual increase in overall population numbers. D) Improvements in medical techniques led to a dramatic drop in death rates, allowing industrialization to increase. E) Dramatic increases in population occurred when the death rates declined due to improvements in the quality of life. F) The final stage of demographic transition occurs when birth rates outstrip death rates, leading to a new round of population growth.

Questions 26-39

Communicating with the Future

In the 1980s the United States Department of Energy was looking for suitable sites to bury radioactive waste material generated by its nuclear energy programs. The government was considering burying the dangerous waste in deep underground chambers in remote desert areas. The problem, however, was that nuclear waste remains highly radioactive for thousands of years. The commission entrusted with tackling the problem of waste disposal was aware that the dangers posed by radioactive emissions must be communicated to our descendants of at least 10,000 years hence. So the task became one of finding a way to tell future societies about the risk posed by these deadly deposits.
Of course, human society in the distant future may be well aware of the hazards of radiation. Technological advances may one day provide solutions to this dilemma. But the belief in constant technological advancement is based on our perceptions of advances made throughout history and prehistory. We cannot be sure that society won't have slipped backward into an age of barbarism* due to any of several catastrophic events, whether the result of nature such as the onset of a new ice age or perhaps humankind's failure to solve the scourges of war and pollution. In the event of global catastrophe, it is quite possible that humans of the distant future will be on the far side of a broken link of communication and technological understanding.
The problem then becomes how to inform our descendants that they must avoid areas of potential radioactive seepage* given that they may not understand any currently existing language and may have no historical or cultural memory. So, any message dedicated to future reception and decipherment must be as universally understandable as possible.
It was soon realized by the specialists assigned the task of devising the communication system that any material in which the message was written might not physically endure the great lengths of time demanded. The second law of thermodynamics shows that all material disintegrates over time. Even computers that might carry the message cannot be expected to endure long enough. Besides, electricity supplies might not be available in 300 generations. Other media storage methods were considered and rejected for similar reasons.
The task force under the linguist Thomas Sebeok finally agreed that no foolproof way would be found to send a message across so many generations and have it survive physically and be decipherable by a people with few cultural similarities to us. Given this restriction, Sebeok suggested the only possible solution was the formation of a committee of guardians of knowledge. Its task would be to dedicate itself to maintaining and passing on the knowledge of the whereabouts and dangers of the nuclear waste deposits. This so-called atomic priesthood would be entrusted with keeping knowledge of this tradition alive through millennia and in developing the tradition into a kind of mythical taboo forbidding people to tamper in any way with the nuclear waste sites. Only the initiated atomic priesthood of experts would have the scientific knowledge to fully understand the danger. Those outside the priesthood would be kept away by a combination of rituals and legends designed to warn off intruders.
This proposal has been criticized because of the possibility of a break in continuity of the original message. Furthermore, there is no guarantee that any warning or sanction passed on for millennia would be obeyed, nor that it could survive with its original meaning intact. To counterbalance this possibility, Sebeok's group proposed a "relay system" in which information is passed on over relatively short periods of time, just three generations ahead. The message is then to be renewed and redesigned if necessary for the following three generations and so on over the required time span. In this way information could be relayed into the future and avoid the possibility of physical degradation.
A second defect is more difficult to dismiss, however. This is the problem of social exclusiveness brought about through possession of vital knowledge. Critics point out that the atomic priesthood could use its secret knowledge to control those who are scientifically ignorant. The establishment of such an association of insiders holding powerful knowledge not available except in mythic form to nonmembers would be a dangerous precedent for future social developments.

*barbarism: a state of existence in which the experience, habits, and culture of modern life are absent
*seepage: an amount of liquid or gas that flows through another substance

26. The word "chambers" in the passage is closest in meaning to cavities partitions openings fissures

In the 1980s the United States Department of Energy was looking for suitable sites to bury radioactive waste material generated by its nuclear energy programs. The government was considering burying the dangerous waste in deep underground chambers in remote desert areas. The problem, however, was that nuclear waste remains highly radioactive for thousands of years. The commission entrusted with tackling the problem of waste disposal was aware that the dangers posed by radioactive emissions must be communicated to our descendants of at least 10,000 years hence. So the task became one of finding a way to tell future societies about the risk posed by these deadly deposits.

27. What problem faced the commission assigned to deal with the burial of nuclear waste? How to reduce the radioactive life of nuclear waste materials How to notify future generations of the risks of nuclear contamination How to form a committee that could adequately express various nuclear risks How to choose burial sites so as to minimize dangers to people

[Refer to the full passage.]

28. In paragraph 2, the author explains the possible circumstances of future societies to warn us about possible natural catastrophes to highlight humankind's inability to resolve problems to question the value of our trust in technological advances to demonstrate the reason nuclear hazards must be communicated Paragraph 2 is marked with an arrow [->].

-> Of course, human society in the distant future may be well aware of the hazards of radiation. Technological advances may one day provide solutions to this dilemma. But the belief in constant technological advancement is based on our perceptions of advances made throughout history and prehistory. We cannot be sure that society won't have slipped backward into an age of barbarism due to any of several catastrophic events, whether the result of nature such as the onset of a new ice age or perhaps humankind's failure to solve the scourges of war and pollution. In the event of global catastrophe, it is quite possible that humans of the distant future will be on the far side of a broken link of communication and technological understanding.

29. The word "scourges" in the passage is closest in meaning to worries pressures afflictions annoyances

Of course, human society in the distant future may be well aware of the hazards of radiation. Technological advances may one day provide solutions to this dilemma. But the belief in constant technological advancement is based on our perceptions of advances made throughout history and prehistory. We cannot be sure that society won't have slipped backward into an age of barbarism due to any of several catastrophic events, whether the result of nature such as the onset of a new ice age or perhaps humankind's failure to solve the scourges of war and pollution. In the event of global catastrophe, it is quite possible that humans of the distant future will be on the far side of a broken link of communication and technological understanding.

30. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information. A message for future generations must be comprehensible to anyone in the world. A universally understandable message must be deciphered for future generations. Any message that is globally understandable must be received and deciphered. The message that future generations receive and interpret must be dedicated.

The problem then becomes how to inform our descendants that they must avoid areas of potential radioactive seepage given that they may not understand any currently existing language and may have no historical or cultural memory. So, any message dedicated to future reception and decipherment must be as universally understandable as possible.

31. In paragraph 4, the author mentions the second law of thermodynamics to contrast the potential life span of knowledge with that of material objects to give the basic scientific reason behind the breakdown of material objects to show that knowledge can be sustained over millennia to support the view that nuclear waste will disperse with time Paragraph 4 is marked with an arrow [->].

-> It was soon realized by the specialists assigned the task of devising the communication system that any material in which the message was written might not physically endure the great lengths of time demanded. The second law of thermodynamics shows that all material disintegrates over time. Even computers that might carry the message cannot be expected to endure long enough. Besides, electricity supplies might not be available in 300 generations. Other media storage methods were considered and rejected for similar reasons.

32. The word "its" in the passage refers to knowledge guardians committee solution

The task force under the linguist Thomas Sebeok finally agreed that no foolproof way would be found to send a message across so many generations and have it survive physically and be decipherable by a people with few cultural similarities to us. Given this restriction, Sebeok suggested the only possible solution was the formation of a committee of guardians of knowledge. Its task would be to dedicate itself to maintaining and passing on the knowledge of the whereabouts and dangers of the nuclear waste deposits. This so-called atomic priesthood would be entrusted with keeping knowledge of this tradition alive through millennia and in developing the tradition into a kind of mythical taboo forbidding people to tamper in any way with the nuclear waste sites. Only the initiated atomic priesthood of experts would have the scientific knowledge to fully understand the danger. Those outside the priesthood would be kept away by a combination of rituals and legends designed to warn off intruders.

33. In paragraph 5, why is the proposed committee of guardians referred to as the "atomic priesthood"? Because they would be an exclusive religious order Because they would develop mythical taboos surrounding their traditions Because they would use rituals and legends to maintain their exclusiveness Because they would be an exclusive group with knowledge about nuclear waste sites Paragraph 5 is marked with an arrow [->]

-> The task force under the linguist Thomas Sebeok finally agreed that no foolproof way would be found to send a message across so many generations and have it survive physically and be decipherable by a people with few cultural similarities to us. Given this restriction, Sebeok suggested the only possible solution was the formation of a committee of guardians of knowledge. Its task would be to dedicate itself to maintaining and passing on the knowledge of the whereabouts and dangers of the nuclear waste deposits. This so-called atomic priesthood would be entrusted with keeping knowledge of this tradition alive through millennia and in developing the tradition into a kind of mythical taboo forbidding people to tamper in any way with the nuclear waste sites. Only the initiated atomic priesthood of experts would have the scientific knowledge to fully understand the danger. Those outside the priesthood would be kept away by a combination of rituals and legends designed to warn off intruders.

34. The word "sanction" in the passage is closest in meaning to security approval counsel penalty

This proposal has been criticized because of the possibility of a break in continuity of the original message. Furthermore. there is no guarantee that any warning or sanction passed on for millennia would be obeyed, nor that it could survive with its original meaning intact. To counterbalance this possibility, Sebeok's group proposed a "relay system" in which information is passed on over relatively short periods of time. just three generations ahead. The message is then to be renewed and redesigned if necessary for the following three generations and so on over the required time span. In this way information could be relayed into the future and avoid the possibility of physical degradation.

35. According to the author, why did the task force under Sebeok propose a relay system for passing on information? To compensate for the fact that meaning will not be stable over long periods of time To show that Sebeok's ideas created more problems than they solved To contrast Sebeok's ideas with those proposed by his main critics To support the belief that breaks in communication are inevitable over time

[Refer to the full passage.]

36. According to paragraph 7, the second defect of the atomic priesthood proposal is that it could lead to the possible misuse of exclusive knowledge the establishment of a scientifically ignorant society the priesthood's criticism of points concerning vital knowledge the nonmembers turning knowledge into dangerous mythical forms Paragraph 7 is marked with an arrow [->].

-> A second defect is more difficult to dismiss, however. This is the problem of social exclusiveness brought about through possession of vital knowledge. Critics point out that the atomic priesthood could use its secret knowledge to control those who are scientifically ignorant. The establishment of such an association of insiders holding powerful knowledge not available except in mythic form to nonmembers would be a dangerous precedent for future social developments.

37. All of the following are mentioned in the passage as difficulties in devising a communication system with the future EXCEPT the loss of knowledge about today's civilization the failure to maintain communication links the inability of materials to endure over time the exclusiveness of a priesthood

[Refer to the full passage.]

38. Look at the four squares [?] that indicate where the following sentence could be added to the passage. Perhaps scientists will find efficient ways to deactivate radioactive materials. Where would the sentence best fit? Choose the letter of the square that shows where the sentence should be added. A B C D

Of course, human society in the distant future may be well aware of the hazards of radiation. [A] Technological advances may one day provide solutions to this dilemma. [B] But the belief in constant technological advancement is based on our perceptions of advances made throughout history and prehistory. [C] We cannot be sure that society won't have slipped backward into an age of barbarism due to any of several catastrophic events, whether the result of nature such as the onset of a new ice age or perhaps humankind's failure to solve the scourges of war and pollution. [D] In the event of global catastrophe, it is quite possible that humans of the distant future will be on the far side of a broken link of communication and technological understanding.

39. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points. Write the letters of the answer chaces in the spaces where they belong. Refer to the full passage. The problem of how to pass on knowledge of the dangers posed by buried radioactive waste was addressed by a commission of experts. * * * Answer Choices A) A task force argued that a select group should be entrusted with passing on knowledge of the dangers of radioactive deposits by using a relay system. B) Electricity supplies may not exist in the future, so computers should not be entrusted with storage of vital information. C) Technological improvements will possibly allow future generations to decontaminate nuclear waste. D) The atomic priesthood proposal has been criticized due to its potential for creating a future society divided into those who hold special knowledge and those who don't. E) The atomic priesthood would develop rituals and legends designed to warn off trespassers into the nuclear burial sites. F) Various means of storing and passing on information are unreliable over time because of the difficulty of communicating with future societies and the likely physical decay of storage media.