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: How many odd 4-digit positive integers R that are multiples of 5 can be formed without using the digit 3?

 Option A: 648

 Option B: 729

 Option C: 900

 Option D: 1296

 Option E: 3240

A: Option A
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Q: Question: The sum of the digits of a two-digit number is 15 and the difference between the digits is 3. What is the two-digit number?

 Option A: 69

 Option B: 78

 Option C: 96

 Option D: Cannot be determined

 Option E: None of these

A: Option D
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Q: Question: If 7 boys meet at a reunion and each boy shakes hands exactly once with each of the others, then what is the total number of handshakes

 Option A: 21

 Option B: 42

 Option C: 43

 Option D: 44

 Option E: 45

A:
Option A
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