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'.

Q: Problem: a = 4 ^ 15 - 625 ^ 3 and a / x is an integer , where x is a positive integer greater than 1 , such that it does not have a factor p such that 1 < p < x , then how many different values for x are possible ? 
Options: a ) none , b ) one , c ) two , d ) three , e ) four

A: c
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Q: Problem: find the ones digit of 73 ^ 356 
Options: a ) 1 , b ) 5 , c ) 6 , d ) 7 , e ) 9

A: a
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Q: Problem: what is the dividend . divisor 18 , the quotient is 9 and the remainder is 4 
Options: a ) a ) 166 , b ) b ) 148 , c ) c ) 150 , d ) d ) 153 , e ) e ) 158

A:
a
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