instruction:
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'.
question:
Problem: walking with 5 / 4 of my usual speed , i miss the bus by 5 minutes . what is my usual time ? 
Options: a ) 18 , b ) 19 , c ) 20 , d ) 22 , e ) 24
answer:
c


question:
Problem: 45 men working 8 hours per day dig 40 m deep . how many extra men should be put to dig to a depth of 50 m working 6 hours per day ? 
Options: a ) 10 , b ) 20 , c ) 30 , d ) 40 , e ) 50
answer:
c


question:
Problem: a train 100 meters long completely crosses a 300 meters long bridge in 24 seconds . what is the speed of the train is ? 
Options: a ) 60 kmph , b ) 76 kmph , c ) 34 kmph , d ) 43 kmph , e ) 40 kmph
answer:

a