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.

[EX Q]: Problem: a can give b 50 meters start and c 100 meters start in a kilometer race. how much start can b give c in a kilometer race ?
Options: a. 111.12, b. 111.67, c. 111.64, d. 52.63, e. 101.12
[EX A]: d

[EX 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
[EX A]: a

[EX Q]: Problem: for all numbers a and b, the operation is defined by ab = ( a + 2 ) ( b 3 ). if 3 x = 20, then x =
Options: a. 15, b. 6, c. 3, d. 6, e. - 1
[EX A]:
e