You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.
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Question: Question: If |x^2 − 20| = x, which of the following could be the value of x?

 Option A: -5

 Option B: -4

 Option C: 1

 Option D: 4

 Option E: 10

Answer: Option D


Question: Question: If x and y are negative integers, which of the following statements must be true?
I. (-x)^y is positive.
II. (-x)^(-y) is positive.
III. x^(-y) is positive.

 Option A: None

 Option B: II only

 Option C: I and II

 Option D: I and III

 Option E: I, II and III

Answer: Option C


Question: Question: A block of wood has dimensions 10cm x 10cm x 40cm. The block is painted red and then cut evenly at the 20 cm mark, parallel to the sides, to form two rectangular solids of equal volume. What percentage of the surface area of each of the new solids is not painted red?

 Option A: 5%

 Option B: 10%

 Option C: 15%

 Option D: 20%

 Option E: 25%

Answer:
Option B