In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Input: Consider Input: Problem: 120 + 520 ÷ 5.00 = ? 
Options: a ) 100 , b ) 150 , c ) 120 , d ) 520 , e ) none

Output: e


Input: Consider Input: Problem: if 7 ^ k = 2 , then 7 ^ ( 4 k + 2 ) = 
Options: a ) 729 , b ) 754 , c ) 784 , d ) 783 , e ) 108

Output: c


Input: Consider Input: Problem: if the average ( arithmetic mean ) of a and b is 50 and the average of b and c is 70 , what is the value of c − a ? 
Options: a ) 40 , b ) 50 , c ) 90 , d ) 140 , e ) it can not be determined from the information given .


Output: a