Read the following passages and then choose the best answer for each question.

Passage 17

It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems  for a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately,  in the death of a species.

The fossil record reveals that extinction has occurred throughout the history of Earth.  Recent analyses have also revealed that on some occasions many species became extinct  at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise  of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton  in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.

One interesting, and controversial, finding  is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.

1. The word “it” in line 3 refers to

2. The word “ultimately” in line 8 is closest in meaning to

3. What does the author say in paragraph 1 regarding most species in Earth’s history

4. Which of the following is NOT mentioned in paragraph 1 as resulting from rapid ecological change?

5. The word “demise” in line 12 is closest in meaning to

6. Why is “ plankton” mentioned in line 17?

7. According to paragraph 2, evidence from fossils suggests that

8. The word “finding” in line 20 is closest in meaning to

9. Which of the following can be in

10. In paragraph 3, the author makes which of the following statements about a species’ survival?

Passage 18

The Moon, which has undergone a distinct and complex geological history, presents a striking appearance. The moon may be divided into two major terrains: the maria (dark  lowlands) and the terrace( bright highlands). The contrast in the reflectivity (the capability of reflecting light ) of these two terrains suggested to many early observers that the two terrains might have different compositions, and this supposition was confirmed by  missions to the Moon such as Surveyor and Apollo. One of the most obvious differences between the terrains is the smoothness of the maria in contrast to the roughness of the  highlands. This roughness is mostly caused by the abundance of craters; the highlands are  completely covered by large craters( greater than 40-50 km in diameter), while the craters  of the maria tend to be much smaller. It is now known that the vast majority of the Moon’s craters were formed by the impact of solid bodies with the lunar surface.

Most of the near side of the Moon was thoroughly mapped and studied from telescopic pictures years before the age of space exploration. Earth-based telescopes can resolve objects as small as a few hundred meters on the lunar surface. Close observation of  craters, combined with the way the Moon diffusely reflects sunlight, led to the

understanding that the Moon is covered by a surface layer, or regolith, that overlies the  solid rock of the Moon. Telescopic images permitted the cataloging of a bewildering array of land forms. Craters were studied for clues to their origin; the large circular maria were seen. Strange, sinuous features were observed in the maria. Although various land forms were catalogued, the majority of astronomers’ attention was fixed on craters and their  origins.

Astronomers have known for a fairly long time that the shape of craters changes as they increase in size. Small craters with diameters of less than 10-15 km have relatively  simple shapes. They have rim crests that are elevated above the surrounding terrain, smooth, bowl-shaped interiors, and depths that are about one-fifth to one-sixth their diameters.  The complexity of shape increases for larger craters.

1. What does the passage mainly discuss?

2. The word ”undergone” in line 1 is closest in meaning to

3. According to the passage, the maria differ from the terrace mainly in terms of

4. The passage supports which of the following statements about the Surveyor and Apollo missions?

5. The word ”vast” in line 10 is closest in meaning to

6. All of the following are true of the maria EXCEPT:

7. All of the following terms are defined in the passage EXCEPT

8. The author mentions “wispy marks” in line 19 as an example of

9. According to the passage, lunar researchers have focused mostly on

10. The passage probably continues with a discussion of

passage 19

Hunting is at best a precarious way of procuring food, even when the diet is supplemented with seeds and fruits. Not long after the last Ice Age, around 7,000 B.C. (during the Neolithic period), some hunters and gatherers began to rely chiefly on agriculture for their sustenance. Others continued the old pastoral and nomadic ways. Indeed, agriculture itself evolved over the course of time, and Neolithic peoples had long known how to grow crops. The real transformation of human life occurred when huge numbers of people began to rely primarily and permanently on the grain they grew and the animals they domesticated.

Agriculture made possible a more stable and secure life. With it Neolithic peoples flourished, fashioning an energetic, creative era. They were responsible for many fundamental inventions and innovations that the modern world takes for granted. First, obviously, is systematic agriculture—that is, the reliance of Neolithic peoples on agriculture as their primary, not merely subsidiary, source of food. Thus they developed the primary economic activity of the entire ancient world and the basis of all modern life. With the settled routine of Neolithic farmers came the evolution of towns and eventually cities. Neolithic farmers usually raised more food than they could consume, and their surpluses permitted larger, healthier populations. Population growth in turn created an even greater reliance on settled farming, as only systematic agriculture could sustain the increased numbers of people. Since surpluses o food could also be bartered for other commodities, the Neolithic era witnessed the beginnings of large-scale exchange of goods. In time the increasing complexity of Neolithic societies led to the development of writing, prompted by the need to keep records and later by the urge to chronicle experiences, learning, and beliefs.

The transition to settled life also had a profound impact on the family. The shared needs and pressures that encourage extended-family ties are less prominent in settled than in nomadic societies. Bonds to the extended family weakened. In towns and cities, the nuclear family was more dependent on its immediate neighbors than on kinfolk.

1. What does the passage mainly discuss? 

2. The word “precarious”  in line 1 is closest in meaning to 

3. The author mentions “seeds and fruits” in line 2 as examples of 

4. The word “settled”  in line 11 is closest in meaning to 

5. According to the passage, agricultural societies produced larger human populations because agriculture 

6. According to the passage, all of the following led to the development of writing EXCEPT the 

7. The word “chronicle”  in line 20 is closest in meaning to 

8. According to the passage, how did the shift to agricultural societies impact people’s family relationships? 

9. The author mentions all of the following as results of the shift to agricultural societies EXCEPT 

10. Which of the following is true about the human diet prior to the Neolithic period? 

passage 20

Archaeological discoveries have led some scholars to believe that the first Mesopotamian inventors of writing may have been a people the later Babylonians called Subarians. According to tradition, they came from the north and moved into Uruk in the south. By about 3100B.C, They were apparently subjugated in southern Mesopotamia by the Sumerians, whose name became synonymous with the region immediately north of the
Persian Gulf, in the fertile lower valleys of the Tigris and Euphrates. Here the Sumerians were already well established by the year 3000B.C. They had invented bronze, an alloy that could be cast in molds, out of which they made tools and weapons. They lived in cities, and they had begun to acquire and use capital. Perhaps most important, the Sumerians adapted writing (probably from the Subarians) into a flexible tool of
communication.

Archacologists have known about the Sumerians for over 150 years. Archacologists working at Nineveh in northern Mesopotamia in the mid-nineteenth century found many inscribed clay tablets. Some they could decipher because the language was a Semitic one (Akkadian), on which scholars had already been working for a generation. But other tablets were inscribed in another language that was not Semitic and previously
unknown. Because these inscriptions mad reference to the king of Sumer and Akkad, a scholar suggested that the mew language be called Sumerian. But it was not until the 1890’s that archaeologists excavating in city-states well to the south o fNieveh found many thousands of tablets inscribed in Sumerian only. Because the Akkadians thought of Sumerian as a classical language (as ancient Greek and Latin are considered today),
they taught it to educated persons and they inscribed vocabulary, translation exercised, and other study aids on tablets. Working from known Akkadian to previously unknown Sumerian, scholars since the 1890’s have learned how to read the Sumerian language moderately well. Vast quantities of tablets in Sumerian have been unearthed during the intervening years from numerous sites.

1. According to the passage, the inventors of written language in Mesopotamia were probably the

2. The word “subjugated” in line 3 is closest in meaning to

3. The phrase “synonymous with”  in line 4 is closest in meaning to

4. According to the passage, by the year 3000 B.C. the Sumerians had already done all of the following EXCEPT:

5. The word “some” in line 11 refers to

6. Which of the following can be inferred from the passage concerning the Sumerians?

7. According to the passage, when did archaeologists begin to be able to understand tablets inscribed in Sumerian?

8. According to the passage, in what way did the Sumerian language resemble ancient Greek and Latin?

9. The word “excavating” in line 16 is closest in meaning to

10. According to the passage, how did archaeologists learn to read the Sumerian language?