14. Armtech， a temporary-employment agency， previously gave its employees 2.5 paid vacation days after each 700 hours worked. Armtech's new policy is to give its employees 5.0 paid vacation days after each 1，200 hours worked. Therefore， this new policy is more generous to Armtech employees in giving them more vacation days per hour worked than the old policy did.
Which of the following is an assumption on which the argument depends?
(A) Most current Armtech employees approve of the company's new vacation policy.
(B) A few Armtech employees leave the company before having worked 700 hours.
(C) Most Armtech employees were not aware that the company planned to change its vacation policy until after it had already done so.
(D) A significant portion of Armtech employees stay with the company long enough to work for 1，200 hours.
(E) Armtech's new vacation policy closely matches the vacation policies of competing temporary employment agencies.
15. The global population of frogs has declined in recent years while the amount of ultraviolet radiation reaching the Earth has increased. Since the genetic material in frog eggs is harmed when exposed to ultraviolet radi-ation， and since the eggs themselves are not protected by shells or leathery coverings but are gelatinous， the frog population decline is probably due， at least in part， to the ultraviolet radiation increase.
Which of the following， if true， provides the strongest support for the argument?
(A) Even in those regions where there has been no significant increase in ultraviolet radiation， only a small proportion of the frog eggs that are laid ever hatch.
(B) In areas where there has been the least decline in frog populations， populations of species of insects that frogs eat have decreased.
(C) The eggs of frog species whose populations are declining tend to have higher concentrations of damaging pesticides than do the eggs of frog species whose populations have not declined.
(D) In many places where turtles， which lay eggs with tough， leathery coverings， share habitats with frogs， turtle populations are also in decline.
(E) Populations of frog species that hide their eggs beneath rocks or under sand have declined considerably less than have populations of frog species that do not cover their eggs.
16. To improve productivity， manufacturing companies have recently begun restructuring work to produce more goods with fewer assembly-line workers， and the companies have laid off many workers as a consequence. The workers laid off have been those with the least seniority(time on the job)， generally the younger workers.
The statements above， if true， most strongly support which of the following as a conclusion?
(A) The products manufactured by the companies are not undergoing design changes while the manufacturing jobs are being restructured.
(B) When assembly-line workers have made sug-gestions for improvements in manufacturing processes， some suggestions have been implemented， but many have not.
(C) Assembly-line workers now need increased reading and mathematical skills to do their jobs.
(D) Some of the innovations in assembly-line processes and procedures that were made to increase productivity have instead proved to be counterproductive.
(E) The manufacturing companies are increasing the average age of their assembly-line workforce while still seeking to increase production.
17. During the nineteenth century， Britain's urban popu-lation increased as its rural population diminished. A historian theorizes that， rather than industrialization's being the cause， this change resulted from a series of migrations to urban areas， each occasioned by a depression in the agrarian economy. To test this hypoth-esis， the historian will compare economic data with population census data.
The historian's hypothesis would be most strongly supported if which of the following were found to be true?
(A) The periods of greatest growth in the industrial economy were associated with a relatively rapid decline in the rural population.
(B) The periods of greatest weakness in the agrarian economy were associated with relatively slow growth in the population as a whole.
(C) Periods when the agrarian economy was compar-atively strong and the industrial economy com-paratively weak were associated with a particu-larly rapid decline in the rural population.
(D) Periods when the agrarian and industrial econo-mies were both strong were associated with particularly rapid growth in the urban popula-tion.
(E) The periods of greatest strength in the agrarian economy were associated with relatively slow growth in the urban population.
参考答案： 14.D 15.E 16.E 17.E