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 average of first ten prime numbers which are odd is?

 Option A: 15.5

 Option B: 15.7

 Option C: 15.2

 Option D: 15.8

 Option E: 15.1

A: Option D
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Q: Question: If N = 2^0.1 and N^b = 16, b must equal

 Option A: 3/80

 Option B: 3/5

 Option C: 40

 Option D: 5/3

 Option E: 80/3

A: Option C
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Q: Question: How long will it take for a sum of money to grow from Rs.3000 to Rs.18,000, if it is invested at 5% p.a simple interest?

 Option A: 8 years

 Option B: 64 years

 Option C: 100 years

 Option D: 56 years

 Option E: None

A:
Option C
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