12. Approximately two hundred brands of personal computers are being manufactured, but we currently limit our inventory to only the eight most popular brands. We plan to increase greatly the number of computers we sell by expanding our inventory to include the ten best-selling brands.
Which of the following, if true, points out a major weakness of the plan above?
(A) The capabilities of three most popular personal computers add to be approximately equivalent, with no brand having consistent superiority in all respects.
(B) The seven most popular brands of personal computers account for almost all computers sold.
(C) As the users of personal computers become more sophisticated, they are more willing to buy less well-known brands of computers.
(D) Less popular brands of computers often provide less profit to the retailer because prices must be discounted to attract customers.
(E) The leading brand of personal computer has been losing sales to less popular brands that offer similar capabilities for less money.
13. Of those person who became teachers in 1968 and who later left the profession, 30 percent today earn salaries above $35,000 a year: of those who became teachers in 1968 and have remained in the profession, only 15 percent today earn salaries above $35,000 a year. These figures indicate how underpaid teachers are today.
The argument above depends on which of the following assumptions about the persons for whom statistics are cited?
(A) At least one-third of the group of persons who have remained in teaching would today be earning more than $35,000 a year if they had left teaching.
(B) The group of persons who left teaching and the group who did not are comparable in terms of factors that determine how much people outside the teaching profession are paid.
(C) Most of those persons who left teaching did so entirely because of the low salaries teachers earn.
(D) As a group, those persons who have remained in teaching are abler and more dedicated than the group of persons who left teaching.
(E) The group of persons who left teaching and who today earn more than $35,000 a year were more capable teachers than the group who remained in the profession.
14. Some analysts maintain that an embargo by country Litora on the export of a strategic metal to country Zenda, if imposed, would drive up the price of the metal in Zenda at least tenfold. They note that few other countries export the metal and that, with an embargo, Zenda might have to depend on as-yet-unexploited domestic sources of the metal.
Which of the following, if true, constitutes the most serious objection to the analysis above?
(A) Litora’s economy depends heavily on foreign currency earned by the export of the strategic metal to other countries.
(B) There are foreign-policy steps that Zenda could take to appease Litora and avoid being subjected to an embargo on the metal.
(C) Geologists believe that additional deposits of the metal could possibly be found within the territory of Litora.
(D) Only a small proportion of Zenda’s import expenditures is devoted to the import of the metal from Litora.
(E) In case of an embargo, Zenda could buy the metal indirectly from Litora on the world market at a less than one-third increase in cost.
15. The government should stop permitting tobacco companies to subtract advertising expenses from their revenues in calculating taxable income. Tobacco companies would then have to pay more taxes. As a consequence, they would raise the prices of their products and this price increase would raise the prices of their products and this price increase would discourage tobacco use.
Which of the following is an additional premise required by the argument above?
(A) Tobacco companies would not offset the payment of extra taxes by reducing costs in other areas.
(B) Tobacco companies would not continue to advertise if they were forced to pay higher taxes.
(C) People would not continue to buy tobacco products if these products were no longer advertised.
(D) The money the government would gain as a result of the increase in tobacco companies’ taxable income would be used to educate the public about the dangers of tobacco use.
(E) The increase in taxes paid by tobacco companies would be equal to the additional income generated by raising prices.
16. Instead of blaming an airline accident on pilot error, investigators should find out why the error was made by analyzing airplane design, airline management, and pilot-training programs. For only then can changes be made to ensure that the same type of error does not recur and cause another accident.
Which of the following is a presupposition of the argument above?
(A) Pilot error is not a contributing factor in most airline accidents.
(B) Airline companies themselves should be the agents who investigate airline accidents.
(C) Stricter government regulation of airline companies will make air travel significantly safer.
(D) Investigators of airline accidents should contribute to the prevention of future accidents.
(E) Most pilots who make errors in flying will repeat their errors unless they are retrained.
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