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'.

[EX Q]: Problem: a train 250 m long is running at a speed of 45 km / hr . in what time will it pass a bridge 150 m long ?
Options: a ) 45 sec , b ) 42 sec , c ) 32 sec , d ) 48 sec , e ) 25 sec
[EX A]: c

[EX Q]: Problem: a boat running downstream covers a distance of 12 km in 2 hours while for covering the same distance upstream , it takes 3 hours . what is the speed of the boat in still water ?
Options: a ) 8 kmph , b ) 5 kmph , c ) 4 kmph , d ) 6 kmph , e ) 7 kmph
[EX A]: b

[EX Q]: 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 35 miles per hour . how many miles from the station was train a overtaken by train b ?
Options: a ) 420 , b ) 450 , c ) 480 , d ) 510 , e ) 540
[EX A]:
a