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: bob wants to run a mile in the same time as his sister. if bob ’ s time for a mile is currently 11 minutes 20 seconds and his sister ’ s time is currently 9 minutes 36 seconds, by what percent does bob need to improve his time in order run a mile in the same time as his sister ?
Options: a. 3 %, b. 5 %, c. 8 %, d. 10 %, e. 15 %
[A]: e


[Q]: Problem: if the radius of a cylinder is made 3 times and so is the height, what is the new volume of the cylinder divided by the old one ?
Options: a. 27., b. 2., c. 6., d. 4., e. 10.
[A]: a


[Q]: Problem: x starts a business with rs. 45000. y joins in the business after 4 months with rs. 30000. what will be the ratio in which they should share the profit at the end of the year ?
Options: a. 1: 2, b. 2: 1, c. 1: 3, d. 3: 1, e. 9: 4
[A]:
e