题目列表

序号 题目内容
0 Many athletes inhale pure oxygen after exercise in an attempt to increase muscular reabsorption of oxygen. Measured continuously after exercise, however, the blood lactate levels of athletes who inhale pure oxygen are practically identical, on average, to those of athletes who breathe normal air. The lower the blood lactate level is, the higher the muscular reabsorption of oxygen is. If the statements above are all true, they most strongly support which of the following conclusions?
0 Outbreaks of Rift Valley fever occur irregularly in East Africa, several years apart. When outbreaks do occur, they kill thousands of cattle. A livestock vaccine against the disease exists but is rarely used. It is too expensive for farmers to use routinely, and since it is not effective until a month after vaccination, administering it after an outbreak begins helps very little. Nevertheless, experts predict that use of the vaccine will increase significantly within the next few years. Which of the following, if true, provides the strongest justification for the experts' prediction?
0 Many small roads do not have painted markings along their edges. Clear edge markings would make it easier for drivers to see upcoming curves and to judge the car's position on the road, particularly when visibility is poor, and would therefore seem to be a useful contribution to road safety. However, after Greatwater County painted edge markings on all its narrow, winding roads, the annual accident rate along those roads actually increased slightly. Which of the following, if true, most helps to explain the increase in accident rate?
0 Maize contains the vitamin niacin, but not in a form the body can absorb. Pellagra is a disease that results from niacin deficiency. When maize was introduced into southern Europe from the Americas in the eighteenth century, it quickly became a dietary staple, and many Europeans who came to subsist primarily on maize developed pellagra. Pellagra was virtually unknown at that time in the Americas, however, even among people who subsisted primarily on maize. Which of the following, if true, most helps to explain the contrasting incidence of pellagra described above?
0 Many office buildings designed to prevent outside air from entering have been shown to have elevated levels of various toxic substances circulating through the air inside, a phenomenon known as sick building syndrome. Yet the air in other office buildings does not have elevated levels of these substances, even though those buildings are the same age as the "sick" buildings and have similar designs and ventilation systems. Which of the following, if true, most helps to explain why not all office buildings designed to prevent outside air from entering have air that contains elevated levels of toxic substances?
0 Beginning in 1966 all new cars sold in Morodia were required to have safety belts and power steering. Previously, most cars in Morodia were without these features. Safety belts help to prevent injuries in collisions, and power steering helps to avoid collisions in the first place. But even though in 1966 one-seventh of the cars in Morodia were replaced with new cars, the number of car collisions and collision-related injuries did not decline. Which of the following, if true about Morodia, most helps to explain why the number of collisions and collision-related injuries in Morodia failed to decline in 1966?
0 The faster a car is traveling, the less time the driver has to avoid a potential accident, and if a car does crash, higher speeds increase the risk of a fatality. Between 1995 and 2000, average highway speeds increased significantly in the United States, yet, over that time, there was a drop in the number of car-crash fatalities per highway mile driven by cars. Which of the following, if true about the United States between 1995 and 2000, most helps to explain why the fatality rate decreased in spite of the increase in average highway speeds?
0 Microscopic plants called algae grow inside the top layer of sea ice in the Antarctic if enough sunlight reaches that layer of ice and enough seawater, which contains nutrients, reaches that layer after splashing onto the surface. Even though moderate snow cover reduces the sunlight that filters into the top layer, sea ice with moderate snow cover typically contains even more algae in the top layer than does sea ice with less snow cover. Which of the following, if true, most helps to explain the apparent discrepancy?
0 A popular beach has long had a dolphin feeding program in which fish are given to dolphins several times a day; many dolphins get as much as half of their food each day there. Although dolphins that first benefit from the program as adults are healthy and long-lived, their offspring have a lower life expectancy than offspring of dolphins that feed exclusively in the wild. Which of the following, if true, most helps to explain the lower life expectancy of offspring of dolphins feeding at the beach compared to other young dolphins?
0 In the country of Veltria, the past two years` broad economic recession has included a business downturn in the clothing trade, where sales are down by about 7 percent as compared to two years ago. Clothing wholesalers have found, however, that the proportion of credit extended to retailers that was paid off on time fell sharply in the first year of the recession but returned to its prerecession level in the second year. Which of the following, if true, most helps to explain the change between the first and the second year of the recession in the proportion of credit not paid off on time?
0 The population of elephant seals, reduced by hunting to perhaps a few dozen animals early in this century, has soared under federal protection during the last few decades. However, because the species repopulated itself through extensive inbreeding, it now exhibits a genetic uniformity that is almost unparalleled in other species of mammals, and thus it is in far greater danger of becoming extinct than are most other species. Given the information in the passage above, which of the following is most likely the reason that other species of mammals are less likely than elephant seals to become extinct?
0 Wolves generally avoid human settlements. For this reason, domestic sheep, though essentially easy prey for wolves, are not usually attacked by them. In Hylantia prior to 1910, farmers nevertheless lost considerable numbers of sheep to wolves each year. Attributing this to the large number for wolves, in 1910 the government began offering rewards to hunters for killing wolves. From 1910 to 1915, large numbers of wolves were killed. Yet wolf attacks on sheep increased significantly. Which of the following, if true, most helps to explain the increase in wolf attacks on sheep?
0 Prior to 1980, many American-made cars did not have anti-lock brakes. These brakes help to prevent cars from skidding and spinning out on ice, and would therefore seem to increase driver control. However, after 1980, when all American-made cars were manufactured with anti-lock brakes, the number of U.S. drivers who experience car accidents due to skidding or spinning out on ice increased by 4 percent annually. Which of the following, if true, most helps to explain the increase in the number of drivers who skidded and spun out on ice?
0 A company that invests the necessary infrastructure in a large untapped diamond mine can reap as much as 700% profit in the first year. Some of the largest untapped diamond mines in the world are in the nation of Shagoca. Therefore, the American company that brokers a deal in the capital Conkin that allows it to put the necessary infrastructure in place at those mines stands to reap tremendous profits. Which of the following, if true, most helps to explain why American companies are not eager to invest in infrastructure necessarily for diamond mining in Shagoca?
0 For the United States meat industry, there is good news and bad news. The bad news in that over the last three years people in the United States have been eating less meat. The good news is that during this same time period meat producer's profits have risen steadily. Which of the following, if true during the last three years, contributes most to a resolution of the apparent discrepancy above?
0 The rate at which a road wears depends on various factors, including climate, amount of traffic, and the size and weight of the vehicles using it. The only land transportation to Rittland`s seaport is via a divided highway, one side carrying traffic to the seaport and one carrying traffic away from it. The side leading to the seaport has worn faster, even though each side has carried virtually the same amount of traffic, consisting mainly of large trucks. Which of the following, if true, most helps to explain the difference in the rate of wear?
0 Automobile ownership was rare in Sabresia as recently as 30 years ago, but with continuing growth of personal income there, automobile ownership has become steadily more common. Consequently, there are now far more automobiles on Sabresia's roads than there were 30 years ago, and the annual number of automobile accidents has increased significantly. Yet the annual number of deaths and injuries resulting from automobile accidents has not increased significantly. Which of the following, if true, most helps to explain why deaths and injuries resulting from automobile accidents have not increased significantly?
0 Which of the following most logically completes the passage? Using new detection techniques, researchers have found trace amounts of various medicinal substances in lakes and rivers. Taken in large quantities, these substances could have serious health effects, but they are present in quantities far too low to cause any physiological response in people who drink the water or bathe in it. Nevertheless, medical experts contend that eliminating these trace amounts from the water will have public health benefits, since __________.
0 Which of the following most logically completes the passage? A business analysis of the Appenian railroad system divided its long-distance passenger routes into two categories: rural routes and interurban routes. The analysis found that, unlike the interurban routes, few rural routes carried a high enough passenger volume to be profitable. Closing unprofitable rural routes, however, will not necessarily enhance the profitability of the whole system, since_________.
0 Conventional wisdom suggests vaccinating elderly people first in flu season, because they are at greatest risk of dying if they contract the virus. This year's flu virus poses particular risk to elderly people and almost none at all to younger people, particularly children. Nevertheless, health professionals are recommending vaccinating children first against the virus rather than elderly people. Which of the following, if true, provides the strongest reason for the health professionals' recommendation?

9362

新增题目0

备考考生总人数

6882949

做题总数

2505393436