18. Manager: Accounting and Billing are located right next to each other and the two departments do similar kinds of work; yet expenditures for clerical supplies charged to Billing are much higher. Is Billing wasting supplies?
Head of Billing: Not at all.
Which of the following, if true, best supports the position of the Head of Billing?
(A) There are more staff members in Accounting than in Billing.
(B) Two years ago, expenditures in Accounting for clerical supplies were the same as were expenditures that year in Billing for clerical supplies.
(C) The work of Billing now requires a wider variety of clerical supplies than it did in the past.
(D) Some of the paper-and-pencil work of both Accounting and Billing has been replaced by work done on computers.(E)
(E) Members of Accounting found the clerical supplies cabinet of Billing more convenient to go to for supplies than their own department’s cabinet.
19. Most geologists believe oil results from chemical transformations of hydrocarbons derived from organisms buried under ancient seas. Suppose, instead, that oil actually results from bacterial action on other complex hydrocarbons that are trapped within the Earth. As is well known, the volume of these hydrocarbons exceeds that of buried organisms. Therefore, our oil reserves would be greater than most geologists believe.
Which of the following, if true, gives the strongest support to the argument above about our oil reserves?
(A) Most geologists think optimistically about the Earth’s reserves of oil.
(B) Most geologists have performed accurate chemical analyses on previously discovered oil reserves.
(C) Ancient seas are buried within the Earth at many places where fossils are abundant.
(D) The only bacteria yet found in oil reserves could have leaked down drill holes from surface contaminants.(E)
(E) Chemical transformations reduce the volume of buried hydrocarbons derived from organisms by roughly the same proportion as bacterial action reduces the volume of other complex hydrocarbons.
20. The wild mouflon sheep of the island of Corsica are direct descendants of sheep that escaped from domestication on the island 8,000 years ago. They therefore provide archaeologists with a picture of what some early domesticated sheep looked like, before the deliberate selective breeding that produced modern domesticated sheep began.
The argument above makes which of the following assumptions?
(A) The domesticated sheep of 8,000 years ago were quite dissimilar from the wild sheep of the time.
(B) There are no other existing breeds of sheep that escaped from domestication at about the same time as the forebears of the mouflon.
(C) Modern domesticated sheep are direct descendants of sheep that were wild 8,000 years ago.
(D) Mouflon sheep are more similar to their forebears of 8,000 years ago than modern domesticated sheep are to theirs.(D)
(E) The climate of Corsica has not changed at all in the last 8,000 years.
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