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'.
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Question: Problem: in a group of ducks and cows , the total number of legs are 36 more than twice the number of heads . find the total number of cows .
Options: a ) 12 , b ) 14 , c ) 16 , d ) 18 , e ) 20

Answer: d

Question: Problem: a man has some hens and cows . if the number of heads be 60 and the number of feet equals 200 , then the number of hens will be :
Options: a ) 22 , b ) 25 , c ) 24 , d ) 20 , e ) 28

Answer: d

Question: Problem: how many integers between 1 and 10 ^ 20 are such that the sum of their digits is 2 ?
Options: a ) 190 , b ) 210 , c ) 211 , d ) 230 , e ) 231

Answer:
b