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: the speed of the boat in still water in 12 kmph. it can travel downstream through 54 kms in 3 hrs. in what time would it cover the same distance upstream ?
Options: a. 8 hours, b. 6 hours, c. 4 hours, d. 5 hours, e. 9 hours

A: e
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Q: Problem: for each of her sales, a saleswoman receives a commission equal to 20 percent of the first $ 500 of the total amount of the sale, plus 35 percent of the total amount in excess of $ 500. if the total amount of one of her sales was $ 800, the saleswoman ’ s commission was approximately what percent of the total amount of the sale ?
Options: a. 22 %, b. 24 %, c. 25 %, d. 26 %, e. 28 %

A: d
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Q: Problem: in a room with 8 people, 5 people have exactly 1 friend in the room and 4 people have exactly 2 friends in the room ( assuming that friendship is a mutual relationship, i. e. if jane is paul ' s friend, paul is jane ' s friend.. if two individuals are selected from the room at random, what is the probability that those two individuals are not friends ?
Options: a. 5 / 21, b. 3 / 7, c. 4 / 7, d. 5 / 7, e. 25 / 28

A:
e
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