In this task, you need to provide the correct option for a given problem from the provided options.

Q: Problem: in gabriel ' s sheep herd , every sheep has either fleas or lice or both . half of the sheep have lice , and 84 sheep have both pests . if 94 sheep have lice , how many sheep have only fleas ? 
Options: a ) 10 , b ) 20 , c ) 84 , d ) 94 , e ) 178

A: a
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Q: Problem: the compound ratio of 5 : 6 , 3 : 2 and 4 : 5 is ? 
Options: a ) 3 : 5 , b ) 2 : 7 , c ) 1 : 1 , d ) 1 : 4 , e ) none

A: c
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Q: Problem: if the ratio of a to b is 7 to 3 and the ratio of b to c is 1 to 5 , what is the ratio of a to c ? 
Options: a ) 4 / 15 , b ) 1 / 3 , c ) 2 / 5 , d ) 4 / 5 , e ) 7 / 15

A:
e
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