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 van takes 5 hours to cover a distance of 495 km. what speed in kph should the van maintain to cover the same distance in 3 / 2 of the previous time ?
Options: a. 60, b. 63, c. 66, d. 69, e. 72
[A]: c


[Q]: Problem: a train 100 meters long completely crosses a 300 meters long bridge in 36 seconds. what is the speed of the train is ?
Options: a. 32 kmph, b. 76 kmph, c. 34 kmph, d. 43 kmph, e. 40 kmph
[A]: e


[Q]: Problem: a cistern has a leak which would empty the cistern in 20 minutes. a tap is turned on which admits 5 liters a minute into the cistern, and it is emptied in 24 minutes. how many liters does the cistern hold ?
Options: a. 480, b. 487, c. 481, d. 729, e. 600
[A]:
e