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: if a ( a + 2 ) = 99 and b ( b + 2 ) = 99 , where a ≠ b , then a + b = 
Options: a ) - 2 , b ) - 5 , c ) - 8 , d ) - 10 , e ) - 12

A: a
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Q: Problem: how many halves are there in 9 - fourth ? 
Options: a ) 8 , b ) 4.5 , c ) 3.2 , d ) 7 , e ) 3

A: b
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Q: Problem: if 2 x = 4 y = z , what is x - y , in terms of z ? 
Options: a ) z / 4 , b ) z / 2 , c ) z , d ) 2 z , e ) 4 z

A:
a
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