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 man's speed with the current is 20 kmph and speed of the current is 3 kmph. The Man's speed against the current will be

 Option A: 11 kmph

 Option B: 12 kmph

 Option C: 14 kmph

 Option D: 17 kmph

 Option E: None of these

A: Option C
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Q: Question: (3x + 1) (2x - 5) = ax^2 + kx + n . What is the value of a - n + k ?

 Option A: 5

 Option B: 8

 Option C: 9

 Option D: 14

 Option E: 11

A: Option D
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Q: Question: 6% of customers that enter a store on any given day must not pay tax. If 1000 people shop every day, how many people pay taxes in the store every week

 Option A: 6500

 Option B: 6580

 Option C: 7200

 Option D: 7120

 Option E: 6800

A:
Option B
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