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'.

[EX Q]: Problem: if 7 ^ k = 2 , then 7 ^ ( 4 k + 2 ) = 
Options: a ) 729 , b ) 754 , c ) 784 , d ) 783 , e ) 108
[EX A]: c

[EX Q]: Problem: pradeep has to obtain 20 % of the total marks to pass . he got 160 marks and failed by 25 marks . the maximum marks are 
Options: a ) 1925 , b ) 600 , c ) 925 , d ) 1325 , e ) 900
[EX A]: c

[EX Q]: Problem: on a certain date , pat invested $ 6,000 at x percent annual interest , compounded annually . if the total value of the investment plus interest at the end of 10 years will be $ 24,000 , in how many years total will the total value of the investment plus interest increase to $ 48,000 ? 
Options: a ) 15 , b ) 16 , c ) 18 , d ) 20 , e ) 24
[EX A]:
a