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: two friends deepak and rajeev have agreed to meet at a definite spot on a particular day between 9 pm and 10 pm . the first person to come waits for some time and leaves . if the other one does not turn up by that time . if deepak comes first , he waits for 45 minutes and if rajeev comes first , he waits for 15 minutes . what is the probability of meeting between deepak and rajeev if their arrival times are independent of eachother and each person arrives during the indicated period at random ? 
Options: a ) 3 / 4 , b ) 11 / 16 , c ) 7 / 8 , d ) 3 / 16 , e ) 5 / 16

Ex Output:
d


Ex Input:
Problem: how long does a train 110 m long running at the speed of 72 km / hr takes to cross a bridge 112 m length ? 
Options: a ) 82.1 sec , b ) 12.1 sec , c ) 16.1 sec , d ) 11.1 sec , e ) 12.15 sec

Ex Output:
d


Ex Input:
Problem: two trains leave a station traveling in the same direction . train a leaves traveling at a constant speed of 50 mph , while train b leaves traveling at a constant speed of 80 mph . if train b left the station 30 minutes after train a left , in how many minutes will train b overtake train a ? 
Options: a ) 30 , b ) 40 , c ) 50 , d ) 60 , e ) 70

Ex Output:

c