Detailed Instructions: 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: in a kilometer race, if abhishek gives bharti a 40 m start, abhishek wins by 19 sec. but if abhishek gives bharti a 30 sec start, bharti wins by 40 m. find the time taken by bharti to run 5,000 m ?
Options: a. 150 sec, b. 750 sec, c. 450 sec, d. 825 sec, e. none of these
A:
b