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: a and b together can do a piece of work in 10 days . b alone can finish it in 20 days . in how many days can a alone finish the work ? 
Options: a ) 20 , b ) 10 , c ) 15 , d ) 5 , e ) 7

SOLUTION: a

PROBLEM: Problem: cole drove from home to work at an average speed of 60 kmh . he then returned home at an average speed of 90 kmh . if the round trip took a total of 2 hours , how many minutes did it take cole to drive to work ? 
Options: a ) 66 , b ) 70 , c ) 72 , d ) 75 , e ) 78

SOLUTION: c

PROBLEM: Problem: how many seconds will a 400 meter long train take to cross a man walking with a speed of 3 km / hr in the direction of the moving train if the speed of the train is 63 km / hr ? 
Options: a ) 287 , b ) 288 , c ) 900 , d ) 277 , e ) 121

SOLUTION:
c