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.

Q: Question: Factor (x + 4)3 - 9x - 36 =

 Option A: (x - 4

 Option B: (x + 6

 Option C: (x + 4

 Option D: (x + 4

 Option E: None

A: Option D
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Q: Question: A train covers a distance of 12 km in 10 min. If it takes 10 sec to pass a telegraph post, then the length of the train is?

 Option A: 100

 Option B: 110

 Option C: 200

 Option D: 130

 Option E: 140

A: Option C
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Q: Question: In one hour, a boat goes 14 km/hr along the stream and 8 km/hr against the stream. The speed of the boat in still water (in km/hr) is:

 Option A: 14 km/hr

 Option B: 13 km/hr

 Option C: 12 km/hr

 Option D: 11 km/hr

 Option E: 10 km/hr

A:
Option D
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