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: what is the smallest positive integer x such that 66 - x is the cube of a positive integer
Options: a. 5, b. 7, c. 47, d. 9, e. 2
[EX A]: e

[EX Q]: Problem: a 270 metres long bullet train running at the speed of 120 kmph crosses another bullet train running in opposite direction at the speed of 80 kmph in 9 seconds. what is the length of the other bullet train ?
Options: a. 226, b. 230, c. 430, d. 310, e. 260
[EX A]: b

[EX Q]: Problem: a car started running at a speed of 30 km / hr and the speed of the car was increased by 2 km / hr at the end of every hour. find the total distance covered by the car in the first 11 hours of the journey.
Options: a. 342 km, b. 352 km, c. 642 km, d. 440 km, e. 382 km
[EX A]:
d