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: gold is 10 times as heavy as water and copper is 6 times as heavy as water . in what ratio should these be mixed to get an alloy 8 times as heavy as water ? 
Options: a ) 3 : 2 , b ) 1 : 1 , c ) 3 : 1 , d ) 5 : 2 , e ) 4 : 3

A: b
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Q: Problem: if 12 : 8 : : x : 16 , then find the value of x 
Options: a ) 18 , b ) 24 , c ) 28 , d ) 16 , e ) 20

A: b
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Q: Problem: if f ( x ) = ax ^ 2 – 6 x + ax + 1 , then f ( b ) – f ( - b ) will equal : 
Options: a ) 0 , b ) - 12 b + 2 ab , c ) 2 ab ^ 4 – 8 b ^ 2 – 6 , d ) - 2 ab ^ 4 + 8 b ^ 2 + 6 , e ) 2 ab ^ 4 – 8 b ^ 2 + 2 ab – 6

A:
b
****