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: how many integers between 1 and 10 ^ 16 are such that the sum of their digits is 2 ? 
Options: a ) 106 , b ) 116 , c ) 126 , d ) 136 , e ) 146

A: d
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Q: Problem: if z is not equal to zero , and z = 6 zs − 9 s 2 − − − − − − − − √ z = 6 zs − 9 s 2 , then z equals : 
Options: a ) s , b ) 3 s , c ) 4 s , d ) - 3 s , e ) - 4 s

A: b
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Q: Problem: a group of 8 friends want to play doubles tennis . how many different ways can the group be divided into 4 teams of 2 people ? 
Options: a ) 420 , b ) 2520 , c ) 168 , d ) 90 , e ) 105

A:
e
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