GMAT逻辑复习资料-逻辑大全分类-Explaination

大豆

大全-16-5.        Archaeologists have found wheeled ceramic toys made by the Toltec, twelfth-century inhabitants of what is now Veracruz. Although there is no archaeological evidence that the Toltec used wheels for anything but toys, some anthropologists hypothesize that wheeled utility vehicles were used to carry materials needed for the monumental structures the Toltec produced.
Which of the following, if true, would most help the anthropologists explain the lack of evidence noted above?
wheeled：有某数量轮子的,   ceramic：陶器的
(A) The Toltec sometimes incorporated into their toys representations of utensils or other devices that served some practical purpose.
(B) Any wheeled utility vehicles used by the Toltec could have been made entirely of wood, and unlike ceramic, wood decays rapidly in the humid climate of Veracruz.
制造wheeled utility vehicles的材质是木头，很容易腐烂，不像陶器那样容易保存。
(C) Carvings in monument walls suggest that the Toltec’s wheeled ceramic toys sometimes had ritual uses in addition to being used by both children and adults as decorations and playthings.
(D) Wheeled utility vehicles were used during the twelfth century in many areas of the world, but during this time wheeled toys were not very common in areas outside Veracruz.
(E) Some of the wheeled ceramic toys were found near the remains of monumental structures.

大豆

大全-16-13.        A severe drought can actually lessen the total amount of government aid that United States farmers receive as a group. The government pays farmers the amount, if any, by which the market price at which crops are actually sold falls short of a preset target price per bushel for the crops. The drought of 1983, for example, caused farm-program payments to drop by $10 billion.
大意：严重干旱会减少政府给农民的补贴（补贴原则：政府补给农民crops的实际售价低于期望售价的部分）。比如，1983年的大旱导致政府补贴减少了1亿。解释干旱为何导致补贴减少。
Given the information above, which of the following, if true, best explains why the drought of 1983 resulted in a reduction in farm-program payments?
(A) Prior to the drought of 1983, the government raised the target price for crops in order to aid farmers in reducing their debt loads.1983年以前的事情无关。
(B) Due to the drought of 1983, United States farmers exported less food in 1983 than in the preceding year. crops是否出口无关（因为出口出是卖啊）。
(C) Due to the drought of 1983, United States farmers had smaller harvests and thus received a higher market price for the 1983 crop than for the larger crop of the preceding year.
由于干旱，农民收成小，因为crops的售价就比收成好的时候高。（实际售价高，那么与期望售价的差距就小，所以补贴就减少了）
(D) Due to the drought of 1983, United States farmers planned to plant smaller crops in 1984 than they had in 1983.(C)
(E) Despite the drought of 1983, retail prices for food did not increase significantly between 1982 and 1983.

大豆

大全-15-7.        A report that many apples contain a cancer-causing preservative called Alar apparently had little effect on consumers. Few consumers planned to change their apple-buying habits as a result of the report. Nonetheless, sales of apples in grocery stores fell sharply in March, a month after the report was issued.
Which of the following, if true, best explains the reason for the apparent discrepancy described above?
(A) In March, many grocers removed apples from their shelves in order to demonstrate concern about their customers’ health.
(B) Because of a growing number of food-safety warnings, consumers in March were indifferent to such warnings.
(C) The report was delivered on television and also appeared in newspapers.
(D) The report did not mention that any other fruit contains Alar, although the preservative is used on other fruit.
(E) Public health officials did not believe that apples posed a health threat because only minute traces of Alar were present in affected apples.

大豆

大全-15-9.        Contrary to earlier predictions, demand for sugarcane has not increased in recent years. Yet, even though prices and production amounts have also been stable during the last three years, sugarcane growers last year increased their profits by more than ten percent over the previous year’s level.
Any of the following statements, if true, about last year, helps to explain the rise in profits EXCEPT:
(A) Many countries that are large consumers of sugarcane increased their production of sugarcane-based ethanol, yet their overall consumption of sugarcane decreased.
(B) Sugarcane growers have saved money on wages by switching from paying laborers an hourly wage to paying them by the amount harvested.
(C) The price of oil, the major energy source used by sugarcane growers in harvesting their crops, dropped by over twenty percent.
(D) Many small sugarcane growers joined together to form an association of sugarcane producers and began to buy supplies at low group rates.
(E) Rainfall in sugarcane-growing regions was higher than it had been during the previous year, allowing the growers to save money on expensive artificial irrigation.

大豆

大全-13-5.        Financing for a large construction project was provided by a group of banks. When the money was gone before the project was completed, the banks approved additional loans. Now, with funds used up again and completion still not at hand, the banks refuse to extend further loans, although without those loans, the project is doomed.
Which of the following, if true, best explains why the bank’s current reaction is different from their reaction in the previous instance of depletion of funds?
(A) The banks have reassessed the income potential of the completed project and have concluded that total income generable would be less than total interest due on the old plus the needed new loans.
(B) The banks have identified several other projects that offer faster repayment of the principal if loans are approved now to get those projects started.
(C) The banks had agreed with the borrowers that the construction loans would be secured by the completed project.
(D) The cost overruns were largely due to unforeseeable problems that arose in the most difficult phase of the construction work.
(E) The project stimulated the development and refinement of several new construction techniques, which will make it easier and cheaper to carry out similar projects in the future.

大豆

大全-13-11.        An experiment was done in which human subjects recognize a pattern within a matrix of abstract designs and then select another design that completes that pattern. The results of the experiment were surprising. The lowest expenditure of energy in neurons in the brain was found in those subjects who performed most successfully in the experiments.
Which of the following hypotheses best accounts for the findings of the experiment?
(A) The neurons of the brain react less when a subject is trying to recognize patterns than when the subject is doing other kinds of reasoning.
(B) Those who performed best in the experiment experienced more satisfaction when working with abstract patterns than did those who performed less well.
(C) People who are better at abstract pattern recognition have more energy-efficient neural connections.
(D) The energy expenditure of the subjects brains increases when a design that completes the initially recognized pattern is determined.
(E) The task of completing a given design is more capably performed by athletes, whose energy expenditure is lower when they are at rest than is that of the general population.

大豆

Questions 3-4 are based on the following.
The proportion of manufacturing companies in Alameda that use microelectronics in their manufacturing processes increased from 6 percent in 1979 to 66 percent in 1990. Many labor leaders say that the introduction of microelectronics is the principal cause of the great increase in unemployment during that period in Alameda. In actual fact, however, most of the job losses were due to organizational changes. Moreover, according to new figures released by the labor department, there were many more people employed in Alameda in the manufacturing industry in 1990 than in 1979.
用ME系统的公司所占比例从1979年的6%上升到1990年的66%，劳工领袖说ME系统的引进是大规模失业的主要原因。然而事实上，大部分工作丢失都是因为结构变化，再者，根据劳工部统计，1990年受佣的人数比1979年要多。为何被雇佣人数增加的同时失业率还增加了。

大豆

大全-12-3.        Which of the following, if true, best reconciles the discrepancy between the increase in unemployment and the increase in jobs in the manufacturing industry of Alameda?
(A) Many products that contain microelectronic components are now assembled completely by machine.
(B) Workers involved in the various aspects of the manufacturing processes that use microelectronic technology need extensive training.
(C) It is difficult to evaluate numerically what impact on job security the introduction of microelectronics in the workplace had before 1979.
(D) In 1990 over 90 percent of the jobs in Alameda’s manufacturing companies were filled by workers who moved to Alameda because they had skills for which there was no demand in Alameda prior to the introduction of microelectronics there.
(E) Many workers who have retired from the manufacturing industry in Alameda since 1979 have not been replaced by younger workers.

大豆

大全-12-5.        The number of musicians employed to play accompaniment for radio and television commercials has sharply decreased over the past ten years. This has occurred even though the number of commercials produced each year has not significantly changed for the last ten years.
Which of the following, if it occurred during the past ten years, would contribute LEAST to an explanation of the facts above?
(A) The type of music most popular for use in commercials has changed from a type that requires a large number of instruments to a type that requires very few instruments.
(B) There has been an increase in the number of commercials that use only the spoken word and sound effects, rather than musical accompaniment.
(C) There has been an increase in the number of commercials that use a synthesizer, an instrument on which one musician can reproduce the sound of many musicians playing together.
(D) There has been an increase in the number of commercials that use prerecorded music as their only source of music.
(E) There has been an increase in the number of commercials that use musicians just starting in the music industry rather than musicians experienced in accompanying commercials.

大豆

大全-11-17.        Since 1975 there has been in the United States a dramatic decline in the incidence of traditional childhood diseases such as measles. This decline has been accompanied by an increased incidence of Peterson’s disease, a hitherto rare viral infection, among children. Few adults, however, have been affected by the disease.
Which of the following, if true, would best help to explain the increased incidence of Peterson’s disease among children?
(A) Hereditary factors determine in part the degree to which a person is susceptible to the virus that causes Peterson’s disease.
(B) The decrease in traditional childhood diseases and the accompanying increase in Peterson’s disease have not been found in any other country.
(C) Children who contract measles develop an immunity to the virus that causes Peterson’s disease.
(D) Persons who did not contract measles in childhood might contract measles in adulthood, in which case the consequences of the disease would generally be more severe.
(E) Those who have contracted Peterson’s disease are at increased risk of contracting chicken pox.