11. Professor Smith published a paper arguing that a chemical found in minute quantities in most drinking water had an adverse effect on the human nervous system. Existing scientific theory held that no such effect was possible because there was no neural mechanism for bringing it about. Several papers by well-known scientists in the field followed, unanimously purporting to prove Professor Smith wrong. This clearly shows that the scientific establishment was threatened by Professor Smith's work and conspired to discredit it.

Which one of the following is the central flaw in the argument given by the author of the passage？

（A） The author passes over the possibility that Professor Smith had much to gain should Professor Smith's discovery have found general acceptance.

（B） The author fails to mention whether or not Professor Smith knew that the existence of the alleged new effect was incompatible with established scientific theory.

（C） The author fails to show why the other scientists could not have been presenting evidence in order to establish the truth of the matter.

（D） The author neglects to clarify what his or her relationship to Professor Smith is.

（E） The author fails to indicate what, if any, effect the publication of Professor Smith's paper had on the public's confidence in the safety of most drinking water.

12. The number of North American children who are obese-that is who have more body fat than do 85 percent of North American children their age -is steadily increasing, according to four major studies conducted over the past 15 years.

If the finding reported above is correct, it can be properly concluded that

（A） when four major studies all produce similar results .those studies must be accurate.

（B） North American children have been progressively less physically active over the past 15 years.

（C） The number of North American children who are not obese increased over the past 15 years.

（D） Over the past 15 years ,the number of North American children who are underweight has declined.

（E） The incidence of obesity in North American children tends to increase as the children grow older.

13. Economist： Money, no matter what its form and in almost every culture in which it has been used, derives its value from its scarcity .whether real or perceived.

Anthropologist： But cowrie shells formed the major currency in the Solomon Island economy of the Kwara'ae ,and unlimited numbers of these shells washed up daily on the beaches to which the kwara'ae had access.

Which one of the following, if true about the Kwara'ae, best serves to resolve the apparently conflicting positions cited above？

（A） During festivals they exchanged strings of cowrie-shell money with each other as part of a traditional ritual that honored their elders.

（B） They considered porpoise teeth valuable, and these were generally threaded on strings to be worn as jewelry.

（C） The shells used as money by men were not always from the same species of cowrie as those used as money by women.

（D） They accepted as money only cowrie shells that were polished and carved by a neighboring people, and such shell preparation required both time and skilled labor.

（E） After Western traders brought money in the form of precious-metal coins to the Solomon Islands. Cowrie-shell money continued to be used as one of the major media of exchange for both goods and services.

14. School superintendent： It is a sad fact that ,until now , entry into the academically best high school in our district has been restricted to the children of people who were wealthy enough to pay the high tuition . Parents who were previously denied the option of sending their children to this school now have this option . since I am replacing the tuition requirement with a requirement that allows only those who live in the neighborhood of the school to attend.

The superintendent's claim about the effect of replacing the tuition requirement relies on the assumption that

（A） the residents of the school's neighborhood tend to be wealthy

（B） people other than those wealthy enough to have paid the old tuition are able to live in the neighborhood of the school.

（C） People less wealthy than those who were able to pay the old tuition are in the majority in the district.

（D） There are no high schools in the district other than the one referred to by the superintendent.

（E） There are many people not wealthy enough to have paid the old tuition who wish to have their children attend the school.

15. The Scorpio Miser with its special high-efficiency engine costs more to buy than the standard Scorpio sports car. At current fuel prices , a buyer choosing the Miser would have to drive it 60,000 miles to make up the difference in purchase price through savings on fuel .It follows that ,if fuel prices fell ,it would take fewer miles to reach the break-even point.

Which one of the following arguments contains an error of reasoning similar to that in the argument above？

（A） The true annual rate of earnings on an interest-bearing account is the annual rate of interest less the annual rate of inflation drops, the rate of interest can be reduced by an equal amount without there being a change in the true rate of earnings.

（B） For retail food stores ,the Polar freezer, unlike the Arctic freezer, provides a consistent temperature that allows the store to carry premium frozen foods. Thus ,if electricity rates fell ,a lower volume of premium-food sales could justify choosing the Polar freezer .

（C） With the Roadmaker ,a crew can repave a mile of decayed road in less time than with the competing model, which is ,however, much less expensive. Reduced staffing levels made possible by the Roadmaker eventually compensate for its higher price .Therefore, the Roadmaker is especially advantageous where average wages are low.

（D） The improve strain the Northland apple tree bears fruit younger and lives longer than the standard strain .The standard strain .The standard strain does grow larger at maturity ,but to allow for this ,standard trees must be spaced farther apart. Therefore , new plantings should all be of the improved strain.

（E） Stocks pay dividends ,which vary from year to year depending on profits made. Bonds pay interest ,which remains constant from year to year . Therefore ,since the interest earned on bonds does not decrease when economic conditions decline , investors decline , investors interested in a reliable income should choose bonds.