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: total 85 matches are conducted in knockout match type . how many players will be participated in that tournament ? 
Options: a ) 85 , b ) 81 , c ) 53 , d ) 82 , e ) 84

A: e
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Q: Problem: if - 3 x + 2 y = 28 and 3 x + 6 y = 84 , what is the product of x and y ? 
Options: a ) 264 . , b ) 428 , c ) 0 , d ) 462 , e ) 642

A: c
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Q: Problem: operation # is defined as : a # b = 4 a ^ 2 + 4 b ^ 2 + 8 ab for all non - negative integers . what is the value of ( a + b ) + 5 , when a # b = 100 ? 
Options: a ) 5 , b ) 8 , c ) 10 , d ) 13 , e ) 17

A:
c
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