20. What does the passage mainly discuss? (A) The history of surveys in North America (B) The principles of conducting surveys (C) Problems associated with interpreting surveys (D) The importance of polls in American political life

21. The word "they" in line 8 refers to (A) North Americans (B) news shows (C) interviews (D) opinions

22. According to the passage, the main disadvantage of person-on-the-street interviews is that they (A) are not based on a&nb, sp;representative sampling (B) are used only on television (C) are not carefully worded (D) reflect political opinions

23. The word "precise" in line 13 is closest in meaning to (A) planned (B) rational (C) required (D) accurate

24. According to paragraph 3, which of the following is most important for an effective survey? (A) A high number of respondents (B) Carefully worded questions (C) An interviewer’s ability to measure respondents’ feelings (D) A sociologist who is able to interpret the results

25. The word "exercise" in line 15 is closest in meaning to (A) utilize (B) consider (C) design (D) defend

26. The word "elicit" in line 18 is closest in meaning to (A) compose (B) rule out (C) predict (D) bring out

27. It can be inferred from the passage that one reason that sociologists may become frustrated with questionnaires is that (A) respondents often do not complete and return questionnaires (B) questionnaires are often difficult to read (C) questionnaires are expensive and difficult to distribute (D) respondents are too eager to supplement questions with their ;own opinions

28. According to the passage, one advantage of live interviews over questionnaires is that live interviews (A) cost less (B) can produce more information (C) are easier to interpret (D) minimize the influence of the researcher

29. The word "probe" in line 25 is closest in meaning to (A) explore (B) influence (C) analyze (D) apply

30. Which of the following terms is defined in the passage? (A) Survey (line 1) (B) Public opinion (line 8) (C) Representative sampling (line 13) (D) Response rate (line 22)

Questions 31-39 Perhaps one of the most dramatic and important changes that took place in the Mesozoic era occurred late in that era, among the small organisms that populate the uppermost, sunlit portion of the oceans--the plankton. The term "plankton" is a broad Line one, designating all of the small plants and animals that float about or weakly propel (5) themselves through the sea. In the late stages of the Mesozoic era. during the Cretaceous period, there was a great expansion of plankton that precipitated skeletons or shells composed of two types of mineral: silica and calcium carbonate. This development radically changed the types of sediments that accumulated on the seafloor, because, while the organic parts of the plankton decayed after the organisms died, their mineralized (10) skeletons often survived and sank to the bottom. For the first time in the Earth’s long history, very large quantities of silica skeletons, which would eventually harden into rock, began to pile up in parts of the deep sea. Thick deposits of calcareous ooze made up of the tiny remains of the calcium carbonate-secreting plankton also accumulated as never before. The famous white chalk cliffs of Dover, in the southeast of England, are just one (15) example of the huge quantities of such material that amassed during the Cretaceous period; there are many more. Just why the calcareous plankton were so prolific during the latter part of the Cretaceous period is not fully understood. Such massive amounts of chalky sediments have never since been deposited over a comparable period of time. The high biological productivity of the Cretaceous oceans also led to ideal conditions (20) for oil accumulation. Oil is formed when organic material trapped in sediments is slowly buried and subjected to increased temperatures and pressures, transforming it into petroleum. Sediments rich in organic material accumulated along the margins of the Tethys Seaway, the tropical east-west ocean that formed when Earth’s single landmass (known as Pangaea) split apart during the Mesozoic era. Many of today’s important oil (25) fields are found in those sediments--in Russia, the Middle East, the Gulf of Mexico, and in the states of Texas and Louisiana in the United States.