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 walks at 10 kmph and 4 hours after his start, b cycles after him at 20 kmph. how far from the start does b catch up with a ?
Options: a. 100 km, b. 150 km, c. 80 km, d. 120 km, e. 200 km

A: c
****
Q: Problem: in a certain deck of cards, each card has a positive integer written on it, in a multiplication game a child draws a card and multiplies the integer on the card with the next large integer. if the each possible product is between 35 and 200, then the least and greatest integer on the card would be
Options: a. 3 and 15, b. 3 and 20, c. 4 and 13, d. 4 and 14, e. 5 and 14

A: e
****
Q: Problem: a store reported total sales of $ 460 million for february of this year. if the total sales for the same month last year was $ 320 million, approximately what was the percent increase in sales ?
Options: a. 2 %, b. 17 %, c. 44 %, d. 65 %, e. 83 %

A:
c
****