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: train a leaves the station traveling at 30 miles per hour . two hours later train leaves the same station traveling in the same direction at 36 miles per hour . how many miles from the station was train a overtaken by train b ?
Options: a ) 320 , b ) 360 , c ) 400 , d ) 440 , e ) 480
b

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
a

Problem: a man sitting in a train which is traveling at 55 kmph observes that a goods train , traveling in opposite direction , takes 10 seconds to pass him . if the goods train is 320 m long , find its speed
Options: a ) 52 kmph , b ) 56 kmph , c ) 60 kmph , d ) 62 kmph , e ) 72 kmph
c