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: The number of diagonals of a polygon of n sides is given by the formula z=n(n-3)/2. If a polygon has twice as many diagonals as sides, how many sides does it have?

 Option A:  3

 Option B:  5

 Option C:  6

 Option D:  7

 Option E:  8

A: Option B
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Q: Question: How many positive integers G less than 10,000 are such that the product of their digits is 210?

 Option A: 24

 Option B: 30

 Option C: 48

 Option D: 54

 Option E: 72

A: Option D
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Q: Question: Let S be the set of all positive integers that, when divided by 8, have a remainder of 5. What is the 79th number in this set?

 Option A:  605

 Option B:  608

 Option C:  613

 Option D:  616

 Option E:  629

A:
Option E
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