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: what is the rate percent when the simple interest on rs. 810 amount to rs. 155 in 4 years ?
Options: a. 4.78, b. 4.68, c. 4.58, d. 4.48, e. 4.38

Answer: a


Question: Problem: an industrial loom weaves 0.128 metres of cloth every second. approximately, how many seconds will it take for the loom to weave 25 metre of cloth ?
Options: a. 194 seconds, b. 195 seconds, c. 196 seconds, d. 197 seconds, e. none of these

Answer: b


Question: Problem: a person buys an article at $ 600. at what price should he sell the article so as to make a profit of 8 % ?
Options: a. 670, b. 689, c. 648, d. 740, e. 889

Answer:
c