wangyilin888

15. Country Y uses its scarce foreign-exchange reserves to buy scrap iron for recycling into steel. Although the steel thus produced earns more foreign exchange than it costs, that policy is foolish. Country Y’s own territory has vast deposits of iron ore, which can be mined with minimal expenditure of foreign exchange.

Which of the following, if true, provides the strongest support for Country Y’s policy of buying scrap iron broad?
(A) The price of scrap iron on international markets rose significantly in 1987.
(B) Country Y’s foreign-exchange reserves dropped significantly in 1987.
(C) There is virtually no difference in quality between steel produced from scrap iron and that produced from iron ore.
(D) Scrap iron is now used in the production of roughly half the steel used in the world today, and experts predict that scrap iron will be used even more extensively in the future.
(E) Furnaces that process scrap iron can be built and operated in Country Y with substantially less foreign exchange than can furnaces that process iron ore.

wangyilin888

14.(Z)It is crucially important to farmers that the herbicides they use to control weeds not damage their crops. One very effective herbicide is safe for corn, but soybeans are damaged even by the herbicide’s residue, which remains in the soil more than a year after the herbicide is applied. Soybeans and corn are not sown together in the sameriled;nevertheless, most farmers are reluctant to use the herbicide on their corn.

Which of the following, if true, provides the strongest justification for the farmers’ reluctance?

A. The residue of the herbicide in the soil a year after application is
not enough to control most weeds effectively.
B. To maint ain the nutrients in the soil, corn and soybeans are oftenplanted in A riled in alternate years.
C. The demand for soybeans is growing faster than is the demand for corn.
D. For maximum yield, soybean plants are grown closer together to
each other than are corn plants.
E. The application of herbicides is less critical for soybean than forcorn crops.

wangyilin888

13.(Z)In 1960’s studies of rats, scientists found that crowding increases the number of attacks among the animals significantly.  But in recent experiments in which rhesus monkeys were placed in crowded conditions, although there was an increase in instances of “coping” behavior—such as submissive gestures and avoidance of dominant individuals—attacks did not become any more frequent.  Therefore it is not likely that, for any species of monkey, crowding increases aggression as significantly as was seen in rats.

Which of the following, if true, most strengthens the argument?

A.        All the observed forms of coping behavior can be found among rhesus monkeys living in uncrowded conditions.
B.        In the studies of rats, nondominant individuals were found to increasingly avoid dominant individuals when the animals were in crowded conditions.
C.        Rhesus monkeys respond with aggression to a wider range of stimuli than any other monkeys do.
D.        Some individual monkeys in the experiment were involved in significantly more attacks than the other monkeys were.
E.        Some of the coping behavior displayed by rhesus monkeys is similar to ehavior rhesus monkeys use to bring to an end an attack that has begun.

wangyilin888

12.(Z)In polluted environments, dolphins gradually accumulated toxins in their body fat, and the larger the dolphin the more accumulated toxin it can tolerate.  Nearly 80 percent of the toxins a female dolphin has accumulated pass into the fat-rich milk her nursing calf ingests.  Therefore, the unusually high mortality rate among dolphin calves in the industrially contaminated waters along Florida’s Gulf Coast is probably the result of their being poisoned by their mother’s milk.

Which of the following, if true, most strengthens the argument?

A.        The survival rate of firstborn dolphin calves in the area along Florida’s Gulf Coast is highest for those whose mothers were killed before they were weaned.
B.        The rate at which adult dolphins living in the waters along Florida’s Gulf Coast accumulate toxins is no higher than that of adult dolphins in comparably polluted waters elsewhere.
C.        Among dolphin calves born in the area along Florida’s Gulf Coast, the mortality rate is highest among those with living siblings.
D.        As dolphins age, they accumulate toxins from the environment more slowly than when they were young.
E.        Dolphins, like other marine mammals, have a higher proportion of body fat than do most land mammals.

wangyilin888

11.(Z有争议)People who have spent a lot of time in contact with animals often develop
animal-induced allergies, some of them quite serious. In a survey of current
employees in major zoos, about 30 percent had animal-induced allergies.
Based on this sample, experts conclude that among members of the general
population who have spent a similarly large amount of time in close contact
with animals, the percentage with animal-induced allergies is not 30 percent
but substantially more.

Which of the following, if true, provides the strongest grounds for the experts’
conclusion?
A.        A zoo employee who develops a serious animal-induced allergy is very
likely to switch to some other occupation.
B.        A zoo employee is more likely than a person in the general population
to keep one or more animal pets at home
C.        The percentage of the general population whose level of exposure to
animals matches that of a zoo employee is quite small.
D.        Exposure to domestic pets is, on the whole, less likely to cause animal-
induced allergy than exposure to many of the animals kept in zoos.
E.        Zoo employees seldom wear protective gear when they handle animals
in their care.

wangyilin888

10.(Z) Consumers planning to buy recreational equipment tend to buy higher quality,more expensive equipment when the economy is strong than when it is
weak. Hill and Dale is a business that sells high-quality, expensive camping
and hiking equipment in Boravia. Although all the signs are that Boravia’s
economy is now entering a period of sustained strength, the managers
of the business do not expect a substantial increase in sales.

Which of the following, if true, would provide the strongest justification for the managers’ judgment?

A.        A significant proportion of Hill and Dale’s sales are made tocustomers who enter the store in order to buy one particularitem but, once there, find other items to buy as well.
B.        In Boravia when the economy is strong, those who mightotherwise go camping tend to take vacations overseas.
C.        The economic upturn is likely to allow Boravia’s nati-onal parks, where most of the camping and hiking is done, to receive extra funding to improve their visitor facilities.
D.        Advances in materials technology have led to thedevelopment of hiking and camping equipment thatis more comfortable and lightweight than before.
E.        Many people in Boravia not only are committed to preserving the country’s wilderness areas but also are interested in spending some time in them.

wangyilin888

9. (Z) Highway Official:  When resurfacing our concrete bridges, we should use electrically conductive concrete (ECC) rather than standard concrete.  In the winter, ECC can be heated by passing an electric current through it, thereby preventing ice buildup.  The cost of the electricity needed is substantially lower than the cost of the de-icing salt we currently use.

Taxpayer:  But construction costs for ECC are much higher than for standard concrete, so your proposal is probably not justifiable on economic grounds.

Which of the following, if true, could best be used to support the highway official’s proposal in the face of the taxpayer’s objection?

A. The use of de-icing salt causes corrosion of the reinforcing steel in concrete bridge decks and damage to the concrete itself, thereby considerably shortening the useful life of concrete bridges.
B. Severe icing conditions can cause power outages and slow down the work of emergency crews trying to get power restored.
C. In weather conditions conducive to icing, ice generally forms on the concrete surfaces of bridges well before it forms on parts of the roadway that go over solid ground.
D. Aside from its potential use for de-icing bridges, ECC might also be an effective means of keeping other concrete structures such as parking garages and airport runways ice free.
E. If ECC were to be used for a bridge surface, the electric current would be turned on only at times at which ice was likely to form.

wangyilin888

8. Half of the subjects in an experiment—the experimental group—consumed large quantities of a popular artificial sweetener. Afterward, this group showed lower cognitive abilities than did the other half of the subjects—the control group—who did not consume the sweetener. The detrimental effects were attributed to an amino acid that is one of the sweetener’s principal constituents.

Which of the following, if true, would best support the conclusion that some ingredient of the sweetener was responsible for the experimental results?
(A) Most consumers of the sweetener do not consume as much of it as the experimental group members did.
(B) The amino acid referred to in the conclusion is a component of all proteins, some of which must be consumed for adequate nutrition.
(C) The quantity of the sweetener consumed by individuals in the experimental group is considered safe by federal food regulators.
(D) The two groups of subjects were evenly matched with regard to cognitive abilities prior to the experiment.
(E) A second experiment in which subjects consumed large quantities of the sweetener lacked a control group of subjects who were not given the sweetener.

wangyilin888

7. Many breakfast cereals are fortified with vitamin supplements. Some of these cereals provide 100 percent of the recommended daily requirement of vitamins. Nevertheless, a well-balanced breakfast, including a variety of foods, is a better source of those vitamins than are such fortified breakfast cereals alone.

Which of the following, if true, would most strongly support the position above?

(A) In many foods, the natural combination of vitamins with other nutrients makes those vitamins more usable by the body than are vitamins added in vitamin supplements.
(B) People who regularly eat cereals fortified with vitamin supplements sometimes neglect to eat the foods in which the vitamins occur naturally.
(C)Foods often must be fortified with vitamin supplements because naturally occurring vitamins are removed during processing.
(D) Unprocessed cereals are naturally high in several of the vitamins that are usually added to fortified breakfast cereals.
(E) Cereals containing vitamin supplements are no harder to digest than similar cereals without added vitamins.

wangyilin888

6. Male bowerbirds construct elaborately decorated nests, or bowers. Basing their judgment on the fact that different local populations of bowerbirds of the same species build bowers that exhibit different building and decorative styles, researchers have concluded that the bowerbirds’ building styles are a culturally acquired, rather than a genetically transmitted, trait.

Which of the following, if true, would most strengthen the conclusion drawn by the researchers?

(A) There are more common characteristics than there are differences among the bower-building styles of the local bowerbird population that has been studied most extensively
(B) Young male bowerbirds are inept at bower-building and apparently spend years watching their elders before becoming accomplished in the local bower style.
(C) The bowers of one species of bowerbird lack the towers and ornamentation characteristic of the bowers of most other species of bowerbird.
(D) Bowerbirds are found only in New Guinea and Australia, where local populations of the birds apparently seldom have contact with one another.
(E) It is well known that the song dialects of some songbirds are learned rather than transmitted genetically.