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 train running at the speed of 20 km / hr crosses a post in 10 seconds. what is the length of the train ?
Options: a. 150, b. 250, c. 415, d. 200, e. 312

A: d
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Q: Problem: a certain library assesses fines for overdue books as follows. on the first day that a book is overdue, the total fine is $ 0.09. for each additional day that the book is overdue, the total fine is either increased by $ 0.30 or doubled, whichever results in the lesser amount. what is the total for a book on the fourth day it is overdue ?
Options: a. $ 0.66, b. $ 0.70, c. $ 0.80, d. $ 0.90, e. $ 1.00

A: a
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Q: Problem: what least no. must be subtracted from 101054 so that remaining no. is divisible by 10 ?
Options: a. 6, b. 4, c. 8, d. 5, e. 3

A:
b
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