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'.

Problem: in a river flowing at 2 km / hr , a boat travels 40 km upstream and then returns downstream to the starting point . if its speed in still water be 6 km / hr , find the total journey time .
Options: a ) 10 hours , b ) 12 hours , c ) 14 hours , d ) 15 hours , e ) none of these
d

Problem: 1257 1275 1527 . . . . . . . . . . . . . . . . + 7521 the addition problem above shows 4 of the 24 different integers that can be formed by using each of the digits 1 , 25 and 7 exactly once in each integer . what is the sum t of the 24 integers ?
Options: a ) 26996 , b ) 44406 , c ) 60444 , d ) 66660 , e ) 99990
e

Problem: ( 27 + 243 ) / 48 = ?
Options: a ) 2 2 , b ) 2 3 , c ) 3 2 , d ) 3 3 , e ) 3
e