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 Q]: Problem: the ratio between the speeds of two trains is 7 : 8 . if the second train runs 400 km in 4 hours , what is the the speed of the first train ? 
Options: a ) 87.0 , b ) 87.5 , c ) 87.2 , d ) 87.1 , e ) 87.4
[EX A]: b

[EX Q]: Problem: an electric pump can fill a tank in 6 hours . because of a leak in the tank , it took 12 hours to fill the tank . if the tank is full , how much time will the leak take to empty it ? 
Options: a ) 10 hours , b ) 12 hours , c ) 8 hours , d ) 5 hours , e ) 15 hours
[EX A]: b

[EX Q]: Problem: riya and priya set on a journey . riya moves eastward at a speed of 20 kmph and priya moves westward at a speed of 30 kmph . how far will be priya from riya after 30 minutes 
Options: a ) 25 kms , b ) 10 kms , c ) 50 kms , d ) 30 kms , e ) 40 kms
[EX A]:
a