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 numbers from 10 to 1000 are exactly divisible by 9 ? 
Options: a ) 100 , b ) 10 , c ) 11 , d ) 12 , e ) 14

A: a
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Q: Problem: find the smallest positive integer n such that 11 n - 1 is divisible by 105 . 
Options: a ) 3 , b ) 4 , c ) 5 , d ) 6 , e ) 7

A: d
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Q: Problem: in digging a pond 20 m * 15 m * 5 m the volumes of the soil extracted will be ? 
Options: a ) 3387 , b ) 1000 , c ) 2866 , d ) 1500 , e ) 1121

A:
d
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