Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

Q: Problem: for each color copy, print shop x charges $ 1.20 and print shop y charges $ 1.70. how much greater is the charge for 40 color copies at print shop y than at print shop x ?
Options: a. $ 14, b. $ 16, c. $ 18, d. $ 20, e. $ 22

A: d
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Q: Problem: a sum of money at simple interest amounts to rs. 720 after 2 years and to rs. 1020 after a further period of 5 years. the sum is :
Options: a. 400, b. 500, c. 600, d. 700, e. 800

A: c
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Q: Problem: what is the dividend. divisor 13, the quotient is 17 and the remainder is 1
Options: a. 222, b. 224, c. 226, d. 228, e. 230

A:
a
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