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


[Q]: Problem: when 52416 is divided by 312 , the quotient is 168 . what will be the quotient when 52.416 is divided by 0.68 ? 
Options: a ) 5 , b ) 6 , c ) 4 , d ) 3 , e ) 8
[A]: d


[Q]: Problem: a car averages 55 mph for the first 4 hours of a trip and averages 70 mph for each additional hour . the average speed for the entire trip was 60 mph . how many hours long is the trip ? 
Options: a ) 6 , b ) 8 , c ) 11 , d ) 12 , e ) 14
[A]:
a