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'.

[Q]: Problem: if a train , travelling at a speed of 180 kmph , crosses a pole in 5 sec , then the length of train is ? 
Options: a ) 250 m , b ) 112 m , c ) 117 m , d ) 125 m , e ) 123 m
[A]: a


[Q]: Problem: in a 80 meters race a beats b by 56 m or 7 seconds . a ' s time over the course is : 
Options: a ) 3 seconds , b ) 12 seconds , c ) 10 seconds , d ) 18 seconds , e ) 28 seconds
[A]: a


[Q]: Problem: a man can do a job in 15 days . his father takes 10 days and his son finishes it in 25 days . how long will they take to complete the job if they all work together ? 
Options: a ) 6.3 , b ) 6.9 , c ) 7.1 , d ) 6.1 , e ) 6.2
[A]:
c