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: the age of somu is one - third his father ' s . 10 years back he was one - fifth of his father ' s age . what is his persent age ? 
Options: a ) 11 , b ) 13 , c ) 14 , d ) 12 , e ) 20

A: e
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Q: Problem: the population of a city increases by 7 % per year but due to migration it decrease by 1 % per years . what will be the percentage increase in population in 3 years ? 
Options: a ) 9 % , b ) 9.10 % , c ) 27 % , d ) 12 % , e ) none of these

A: b
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Q: Problem: how many digits 2 ^ 1000 has ? 
Options: a ) 31 , b ) 35 , c ) 50 , d ) 99 , e ) 310

A:
e
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