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 cost price of a radio is rs. 1800 and it was sold for rs. 1430, find the loss % ?
Options: a. 18 %, b. 20.5 %, c. 30 %, d. 45 %, e. 12 %

A: b
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Q: Problem: it is only in the second option we find the sentence a in continuation with the opening sentence d. sentence a alone explains, why the fear has such enormous effect on the human beings.
Options: a. 28, b. 99, c. 728, d. 27, e. 271

A: b
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Q: Problem: a man sitting in a train which is travelling at 64 kmph observes that a goods train travelling in a opposite direction, takes 18 seconds to pass him. if the goods train is 420 m long, find its speed.
Options: a. 32, b. 15, c. 18, d. 20, e. 25

A:
d
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