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

Q: Problem: what is the greatest positive integer e such that 3 ^ e is a factor of 9 ^ 10 ? 
Options: a ) e = 5 , b ) e = 9 , c ) e = 10 , d ) e = 20 , e ) 30

A: d
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Q: Problem: in a graduating class of 232 students , 144 took geometry and 119 took biology . what is the difference between the greatest possible number and the smallest possible number of students that could have taken both geometry and biology ? 
Options: a ) 144 , b ) 119 , c ) 113 , d ) 88 , e ) 31

A: c
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Q: Problem: a bag contains 3 red , 4 blue and 4 green balls . if 2 ballsare picked at random , what is the probability that both are red ? 
Options: a ) 2 / 15 , b ) 2 / 21 , c ) 3 / 55 , d ) 3 / 29 , e ) 4 / 27

A:
c
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