TASK DEFINITION: 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: Problem: two pipes can fill a tank in 18 minutes and 20 minutes . an outlet pipe can empty the tank in 45 minutes . if all the pipes are opened when the tank is empty , then how many minutes will it take to fill the tank ? 
Options: a ) 1 / 15 , b ) 1 / 16 , c ) 1 / 11 , d ) 1 / 10 , e ) 1 / 12

SOLUTION: e

PROBLEM: Problem: what is the length of a bridge ( in meters ) , which a train 156 meters long and travelling at 45 km / h can cross in 30 seconds ? 
Options: a ) 203 , b ) 211 , c ) 219 , d ) 227 , e ) 235

SOLUTION: c

PROBLEM: Problem: two trains are moving in opposite directions at 60 km / hr and 90 km / hr . their lengths are 1.15 km and 0.6 km respectively . the time taken by the slower train to cross the faster train in seconds is ? 
Options: a ) 42 , b ) 9 , c ) 7 , d ) 67 , e ) 15

SOLUTION:
a