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: A table is bought for Rs.400/- and sold at Rs.600/- find gain or loss percentage

Option A: 15%loss

Option B: 10%gain

Option C: 30%gain

Option D: 20%loss

Option E: 50% gain

A: Option E
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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: If each of 4 digit code is formed of integers from 1 to 10, inclusively, and each of the digits are different, how many possible codes are there?

Option A: 6,040

Option B: 6,840

Option C: 6,240

Option D: 5,040

Option E: 4,069

A:
Option D
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