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'.
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Question: Problem: if 15 ! / 3 ^ x is an integer , what is the greatest possible value of x ? 
Options: a ) 3 , b ) 4 , c ) 5 , d ) 6 , e ) 7

Answer: d


Question: Problem: the unit digit in the product ( 784 x 618 x 917 x 463 ) is : 
Options: a ) 5 , b ) 9 , c ) 16 , d ) 2 , e ) 42

Answer: d


Question: Problem: in the coordinate plane , points ( x , 2 ) and ( 4 , y ) are on line k . if line k passes through the origin and has slope 1 / 4 , then x - y = 
Options: a ) 6 , b ) 7 , c ) 8 , d ) 9 , e ) 10

Answer:
b