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: if ( x - 10 ) ( y - 5 ) ( z - 2 ) = 1000 then what is the least value of x + y + z ? if x, y, z are all integer no.
Options: a. 7, b. 8, c. 9, d. 10, e. 11

A: a
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Q: Problem: a train 50 m long takes 6 sec to cross a man walking at 5 kmph in a direction opposite to that of the train. find the speed of the train ?
Options: a. 15 kmph, b. 25 kmph, c. 35 kmph, d. 45 kmph, e. 55 kmph

A: b
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Q: Problem: john builds a square with a side of 12 cm from some wire. if from the same wire, he builds a rectangle with a width of 6 cm, what will be the length of the rectangle ?
Options: ['a. 18 cm', 'b. 19 cm', 'c. 20 cm', 'd. 21 cm', 'e. none']

A:
a
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