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: if w is the product of the integers from 1 to 30 , inclusive , what is the greatest integer k for which 3 ^ k is a factor of w ?
Options: a ) 10 , b ) 12 , c ) 14 , d ) 16 , e ) 18

Answer: c

Question: Problem: in township k each property is taxed at 10 percent of its assessed value . if the assessed value of a property in township k is increased from $ 20,000 to $ 28,000 , by how much will the property tax increase ?
Options: a ) $ 800 , b ) $ 1000 , c ) $ 600 , d ) $ 400 , e ) $ 500

Answer: a

Question: Problem: a man has some hens and cows . if the number of heads be 100 and the number of feet equals 180 , then the number of hens will be :
Options: a ) 22 , b ) 23 , c ) 80 , d ) 90 , e ) 28

Answer:
d