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: working simultaneously and independently at an identical constant rate , 5 machines of a certain type can produce a total of x units of product p in 4 days . how many of these machines , working simultaneously and independently at this constant rate , can produce a total of 2 x units of product p in 2 days ? 
Options: a ) 11 , b ) 13 , c ) 15 , d ) 18 , e ) 20

A: e
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Q: Problem: when positive integer x is divided by positive integer y , the remainder is 9 . if x / y = 96.12 , what is the value of y ? 
Options: a ) 96 , b ) 75 , c ) 48 , d ) 25 , e ) 12

A: b
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Q: Problem: the milk level in a rectangular box measuring 50 feet by 25 feet is to be lowered by 6 inches . how many gallons of milk must be removed ? ( 1 cu ft = 7.5 gallons ) 
Options: a ) 100 , b ) 250 , c ) 750 , d ) 4687.5 , e ) 5635.5

A:
d
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