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: bottle r contains 350 capsules and costs $ 6.25. bottle t contains 130 capsules and costs $ 2.99. what is the difference between the cost per capsule for bottle r and the cost per capsule for bottle t ?
Options: a. $ 0.25, b. $ 0.12, c. $ 0.0052, d. $ 0.003, e. $ 0.002

A: c
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Q: Problem: the mean proportional between 4 and 16 is ?
Options: a. 12, b. 13, c. 14, d. 15, e. 16

A: e
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Q: Problem: line m lies in the xy - plane. the y - intercept of line m is - 2, and line m passes through the midpoint of the line segment whose endpoints are ( 2, 8 ) and ( 144 ). what is the slope of line m ?
Options: a. - 2, b. - 1, c. 0, d. 1, e. 2

A:
d
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