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 certain roller coaster has 6 cars, and a passenger is equally likely to ride in any 1 of the 6 cars each time that passenger rides the roller coaster. if a certain passenger is to ride the roller coaster 6 times, what is the probability that the passenger will ride in each of the 6 cars ?
Options: a. 3 / 1944, b. 1 / 96, c. 2 / 96, d. 1 / 1944, e. 1

A: a
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Q: Problem: 54671 - 14456 - 31466 = ?
Options: a. 2449, b. 5449, c. 8749, d. 8449, e. 6468

A: c
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Q: Problem: how many bricks, each measuring 25 cm x 11.25 cm x 6 cm, will be needed to build a wall of 9 m x 6 m x 22.5 cm ?
Options: a. 6400, b. 6410, c. 6440, d. 7200, e. 6800

A:
d
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