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'.

Problem: two trains are moving in opposite directions at 60 km / hr and 90 km / hr . their lengths are 2.9 km and 1.6 km respectively . the time taken by the slower train to cross the faster train in seconds is ? 
Options: a ) 99 , b ) 277 , c ) 48 , d ) 96 , e ) 108
e

Problem: a pipe can fill a cistern in 33 minutes . find the time in which 1 / 11 part of the cistern will be filled ? 
Options: a ) 5 min , b ) 2 min , c ) 3 min , d ) 1 min , e ) 10 min
c

Problem: two pipes a and b can separately fill a tank in 12 and 15 minutes respectively . a third pipe c can drain off 45 liters of water per minute . if all the pipes are opened , the tank can be filled in 15 minutes . what is the capacity of the tank ? 
Options: a ) 399 , b ) 540 , c ) 772 , d ) 272 , e ) 121

b