11. Red blood cells in which the malarial-fever parasite resides are eliminated from a person’s body after 120 days. Because the parasite cannot travel to a new generation of red blood cells, any fever that develops in a person more than 120 days after that person has moved to a malaria-free region is not due to the malarial parasite.Which of the following, if true, most seriously weakens the conclusion above?
(A) The fever caused by the malarial parasite may resemble the fever caused by flu viruses.
(B) The anopheles mosquito, which is the principal insect carrier of the malarial parasite, has been eradicated in many parts of the world.
(C) Many malarial symptoms other than the fever, which can be suppressed with antimalarial medication, can reappear within 120 days after the medication is discontinued.
(D) In some cases, the parasite that causes malarial fever travels to cells of the spleen, which are less frequently eliminated from a person’s body than are red blood cells.
(E) In any region infested with malaria-carrying mosquitoes, there are individuals who appear to be immune to malaria.
12. Fact 1: Television advertising is becoming less effective: the proportion of brand names promoted on television that viewers of the advertising can recall is slowly decreasing.Fact 2: Television viewers recall commercials aired first or last in a cluster of consecutive commercials far better thanthey recall commercials aired somewhere in the middle.Fact 2 would be most likely to contribute to an explanation of fact 1 if which of the following were also true?
(A) The average television viewer currently recalls fewer than half the brand names promoted in commercials he or she saw.
(B) The total time allotted to the average cluster of consecutive television commercials is decreasing.
(C) The average number of hours per day that people spend watching television is decreasing.
(D) The average number of clusters of consecutive commercials per hour of television is increasing.
(E) The average number of television commercials in a cluster of consecutive commercials is increasing.
13. The number of people diagnosed as having a certain intestinal disease has dropped significantly in a rural county this year, as compared to last year, Health officials attribute this decrease entirely to improved sanitary conditions at water-treatment plants, which made for cleaner water this year and thus reduced the incidence of the disease.Which of the following, if true, would most seriously weaken the health officials’ explanation for the lower incidence of the disease?
(A) Many new water-treatment plants have been built in the last five years in the rural county.
(B) Bottled spring water has not been consumed in significantly different quantities by people diagnosed as having the intestinal disease, as compared to people who did not contract the disease.
(C) Because of a new diagnostic technique, many people who until this year would have been diagnosed as having the intestinal disease are now correctly diagnosed as suffering from intestinal ulcers.
(D) Because of medical advances this year, far fewer people who contract the intestinal disease will develop severe cases of the disease.
(E) The water in the rural county was brought up to the sanitary standards of the water in neighboring counties ten years ago.
14. The price the government pays for standard weapons purchased from military contractors is determined by a pricing method called “historical costing.” Historical costing allows contractors to protect their profits by adding a percentage increase, based on the current rate of inflation, to the previous year’s contractual price.Which of the following statements, if true, is the best basis for a criticism of historical costing as an economically sound pricing method for military contracts?
(A) The government might continue to pay for past inefficient use of funds.
(B) The rate of inflation has varied considerably over the past twenty years.
(C) The contractual price will be greatly affected by the cost of materials used for the products.
(D) Many taxpayers question the amount of money the government spends on military contracts.
(E) The pricing method based on historical costing might not encourage the development of innovative weapons.
15. Some who favor putting governmental enterprises into private hands suggest that conservation objectives would in general be better served if private environmental groups were put in charge of operating and financing the national park system, which is now run by the government.Which of the following, assuming that it is a realistic possibility, argues most strongly against the suggestion above?
(A) Those seeking to abolish all restrictions on exploiting the natural resources of the parks might join the private environmental groups as members and eventually take over their leadership.
(B) Private environmental groups might not always agree on the best ways to achieve conservation objectives.
(C) If they wished to extend the park system, the private environmental groups might have to seek contributions from major donors and the general public.
(D) There might be competition among private environmental groups for control of certain park areas.
(E) Some endangered species, such as the California condor, might die out despite the best efforts of the private environmental groups, even if those groups are not hampered by insufficient resources.
16. A recent spate of launching and operating mishaps with television satellites led to a corresponding surge in claims against companies underwriting satellite insurance. As a result, insurance premiums shot up, making satellites more expensive to launch and operate. This, in turn, has added to the pressure to squeeze more performance out of currently operating satellites.Which of the following, if true, taken together with the information above, best supports the conclusion that the cost of television satellites will continue to increase?
(A) Since the risk to insurers of satellites is spread over relatively few units, insurance premiums are necessarily very high.
(B) When satellites reach orbit and then fail, the causes of failure are generally impossible to pinpoint with confidence.
(C) The greater the performance demands placed on satellites, the more frequently those satellites break down.
(D) Most satellites are produced in such small numbers that no economies of scale can be realized.
(E) Since many satellites are built by unwieldy international consortia, inefficiencies are inevitable.
17. Tocqueville, a nineteenth-century writer known for his study of democracy in the United States, believed that a government that centralizes power in one individual or institution is dangerous to its citizens. Biographers claim that Tocqueville disliked centralized government because he blamed Napoleon’s rule for the poverty of his childhood in Normandy.Which of the following, if true, would cast the most serious doubt on the biographers’ claim?
(A) Although Napoleon was popularly blamed at the time for the terrible living conditions in Normandy, historians now know that bad harvests were really to blame for the poor economic conditions.
(B) Napoleon was notorious for refusing to share power with any of his political associates.
(C) Tocqueville said he knew that if his father had not suffered ill health, his family would have had a steady income and a comfortable standard of living.
(D) Although Tocqueville asserted that United States political life was democratic, the United States of the nineteenth century allowed political power to be concentrated in a few institutions.
(E) Tocqueville once wrote in a letter that, although his childhood was terribly impoverished, it was not different from the experience of his friends and neighbors in Normandy.
18. Radio interferometry is a technique for studying details of celestial objects that combines signals intercepted by widely spaced radio telescopes. This technique requires ultraprecise timing, exact knowledge of the locations of the telescopes, and sophisticated computer programs. The successful interferometric linking of an Earth-based radio telescope with a radio telescope on an orbiting satellite was therefore a significant technological accomplishment.Which of the following can be correctly inferred from the statements above?
(A) Special care was taken in the launching of the satellite so that the calculations of its orbit would be facilitated.
(B) The signals received on the satellite are stronger than those received by a terrestrial telescope.
(C) The resolution of detail achieved by the satellite-Earth interferometer system is inferior to that achieved by exclusively terrestrial systems.
(D) The computer programs required for making use of the signals received by the satellite required a long time for development.
(E) The location of an orbiting satellite relative to locations on Earth can be well enough known for interferometric purposes.
19. Recent estimates predict that between 1982 and 1995 the greatest increase in the number of people employed will be in the category of low-paying service occupations. This category, however, will not increase its share of total employment, whereas the category of high-paying service occupations will increase its share.If the estimates above are accurate, which of the following conclusions can be drawn?
(A) In 1982 more people were working in low-paying service occupations than were working in high-paying service occupations.
(B) In 1995 more people will be working in high-paying service occupations than will be working in low-paying service occupations.
(C) Nonservice occupations will account for the same share of total employment in 1995 as in 1982.
(D) Many of the people who were working in low-paying service occupations in 1982 will be working in high-paying service occupations by 1995.
(E) The rate of growth for low-paying service occupations will be greater than the overall rate of employment growth between 1982 and 1995.
20. For a local government to outlaw all strikes by its workers is a costly mistake, because all its labor disputes must then be settled by binding arbitration, without any negotiated public-sector labor settlements guiding the arbitrators. Strikes should be outlawed only for categories of public-sector workers for whose services no acceptable substitute exists.The statements above best support which of the following conclusions?
(A) Where public-service workers are permitted to strike, contract negotiations with those workers are typically settled without a strike.
(B) Where strikes by all categories of pubic-sector workers are outlawed, no acceptable substitutes for the services provided by any of those workers are available.
(C) Binding arbitration tends to be more advantageous for public-service workers where it is the only available means of settling labor disputes with such workers.
(D) Most categories of public-sector workers have no counterparts in the private sector.
(E) A strike by workers in a local government is unlikely to be settled without help from an arbitrator.
参考答案:
1. D2. E3. E4. D5. C
6. B7. B8. D9. C10. E
11. D12. E13. C14. A15. A
16. C17. C18. E19. A20. C
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