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.
--------
Question: Problem: in one hour, a boat goes 19 km / hr along the stream and 9 km / hr against the stream. the speed of the boat in still water ( in km / hr ) is :
Options: a. 12 kmph, b. 13 kmph, c. 14 kmph, d. 15 kmph, e. 16 kmph

Answer: c


Question: Problem: if p ( a. = 5 / 7 and p ( b. = 2 / 5, find p ( a n b. if a and b are independent events.
Options: a. 7 / 25, b. 3 / 25, c. 8 / 25, d. 2 / 7, e. 3 / 17

Answer: d


Question: Problem: a person buys an article at rs. 480. at what price should he sell the article so as to make a profit of 24 % ?
Options: a. 595, b. 882, c. 772, d. 662, e. 521

Answer:
a