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: two passenger trains start at the same hour in the day from two different stations and move towards each other at the rate of 14 kmph and 21 kmph respectively . when they meet , it is found that one train has traveled 60 km more than the other one . the distance between the two stations is ? 
Options: a ) 477 , b ) 420 , c ) 279 , d ) 276 , e ) 291

A: b
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Q: Problem: two trains are moving in opposite directions with speed of 90 km / hr and 90 km / hr respectively . their lengths are 1.10 km and 0.9 km respectively . the slower train cross the faster train in - - - seconds 
Options: a ) 56 , b ) 40 , c ) 47 , d ) 26 , e ) 25

A: b
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Q: Problem: two trains of equal length , running with the speeds of 60 and 40 kmph , take 50 seconds to cross each other while they are running in the same direction . what time will they take to cross each other if they are running in opposite directions ? 
Options: a ) 10 sec , b ) 11 sec , c ) 77 sec , d ) 99 sec , e ) 67 sec

A:
a
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