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: if 5400 mn = k ^ 4 , where m , n , and k are positive integers , what is the least possible value of m + 2 n ? 
Options: a ) 11 , b ) 18 , c ) 20 , d ) 25 , e ) 40

A: e
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Q: Problem: a retailer bought a hat at wholesale and marked it up 60 % to its initial price of $ 24 . by how many more dollars does he need to increase the price to achieve a 100 % markup ? 
Options: a ) 3 , b ) 4 , c ) 5 , d ) 6 , e ) 7

A: d
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Q: Problem: if x = 7 and y = − 2 , what is the value of ( x − 2 y ) ^ y ? 
Options: a ) − 100 , b ) 0.001 , c ) 0.25 , d ) 4 , e ) 8

A:
b
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