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: a farmer spent $ 35 on feed for chickens and goats. he spent 40 % money on chicken feed, which he bought at a 50 % discount off the full price, and spent the rest on goat feed, which he bought at full price. if the farmer had paid full price for both the chicken feed and the goat feed, what amount would he have spent on the chicken feed and goat feed combined ?
Options: a. $ 37.80, b. $ 49, c. $ 39.20, d. $ 39.50, e. $ 40.60

A: b
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Q: Problem: the average weight of 6 person ' s increases by 4.5 kg when a new person comes in place of one of them weighing 75 kg. what might be the weight of the new person ?
Options: a. 160 kg, b. 175 kg, c. 180 kg, d. 102 kg, e. 190 kg

A: d
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Q: Problem: how many different positive integers are factors of 20 ?
Options: a. 6, b. 8, c. 4, d. 10, e. 12

A:
c
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