In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: a start walking from a place at a uniform speed of 4 kmph in a particular direction . after half an hour , b starts from the same place and walks in the same direction as a at a uniform speed and overtakes a after 1 hour 48 minutes . find the speed of b .
Options: a ) 4.7 kmph , b ) 4.6 kmph , c ) 4 kmph , d ) 7 kmph , e ) 5.3 kmph

Ex Output:
b

Ex Input:
Problem: the speed of a train is 120 kmph . what is the distance covered by it in 40 minutes ?
Options: a ) 50 kmph , b ) 60 kmph , c ) 70 kmph , d ) 80 kmph , e ) 85 kmph

Ex Output:
d

Ex Input:
Problem: a cube of side 5 meter length is cut into small cubes of side 25 cm each . how many such small cubes can be obtained ?
Options: a ) 10781 , b ) 1276 , c ) 1000 , d ) 8000 , e ) 5000

Ex Output:
d