You are given a mathematical question described with an open-ended vocabulary. Questions in this task involve real-world situations, describing a mathematical problem. You are also given 4 or 5 answer options (associated with "A", "B", "C", "D", "E"). Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'. LaTeX mathematical format (the standard way to express mathematical expressions in the typesetting software known as LaTeX) is used to express equations. Each question is solvable with high school math knowledge. Give only one answer for each question.
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Question: If every student in Mr. McNabb's class enjoys making masks, which of the following must be true?
(A)If a student enjoys making masks, then the student is not in Mr. McNabb's class. (B)If a student enjoys making masks, then the student is in Mr. McNabb's class. (C)If a student does not enjoy making masks, then the student is not in Mr. McNabb's class. (D)If a student is not in Mr. McNabb's class, then the student does not enjoy making masks. (E)If a student is in Mr. McNabb's class, then the student does not enjoy making masks.

Answer: C


Question: If 3 kilograms of rose petals are needed to produce 5 grams of perfume, how many kilograms of rose petals are needed to produce 870 grams of perfume?
(A)290 (B)522 (C)870 (D)1,450 (E)2,610

Answer: B


Question: From 1980 to 1990, the value of a share of stock of XYZ Corporation doubled every year. If in 1990 a share of the stock was worth \$80, in what year was it worth \$10?
(A)1984 (B)1985 (C)1986 (D)1987 (E)1988

Answer:
D