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 j and k are integers whose product is 400, which of the following statements must be true?

 Option A: n + k > 0

 Option B: n is not equal to k.

 Option C: Either n or k is a multiple of 10.

 Option D: If n is even, then k is odd.

 Option E: If j is odd, then k is even.

Answer: Option E


Question: Question: A 300 m long train crosses a platform in 33 sec while it crosses a signal pole in 18 sec. What is the length of the platform?

 Option A: 286 m

 Option B: 250 m

 Option C: 277 m

 Option D: 278 m

 Option E: 267 m

Answer: Option B


Question: Question: Rahul rented a power tool from a rental shop. The rent for the tool was $40 for the first hour and $20 for each additional hour. If Rahul paid a total of $160, excluding sales tax, to rent the tool, for how many hours did she rent it?

 Option A: 1

 Option B: 4

 Option C: 9

 Option D: 7

 Option E: 3

Answer:
Option D