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: ray writes a two digit number. he sees that the number exceeds 4 times the sum of its digits by 3. if the number is increased by 18, the result is the same as the number formed by reversing the digits. find the number.
Options: a. 2, b. 5, c. 6, d. 7, e. 8

Answer: b

Question: Problem: there is one 4 - digit whole number n, such that the last 4 digits of n 2 are in fact the original number n
Options: a. 8476, b. 7376, c. 9376, d. 7378, e. 9466

Answer: c

Question: Problem: a ' s speed is 20 / 13 times that of b. if a and b run a race, what part of the length of the race should a give b as a head start, so that b beats a by 80 % of the length of the race ?
Options: a. 44 %, b. 48 %, c. 52 %, d. 42 %, e. 87 %

Answer:
e