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: two trains of equal lengths take 10 sec and 15 sec respectively to cross a telegraph post . if the length of each train be 200 m , in what time will they cross other travelling in opposite direction ? 
Options: a ) 17 sec , b ) 12 sec , c ) 16 sec , d ) 15 sec , e ) 20 sec
[EX A]: e

[EX Q]: Problem: a boeing 757 flies a direct route from dallas , tx , to phoenix , az and then returns to dallas , tx . the flight is 900 miles one way . it took 2 hrs and 15 minutes for the flight to phoenix and 2 hrs for the flight back to dallas . what was the speed of the wind in mph ? 
Options: a ) 20 mph , b ) 25 mph , c ) 30 mph , d ) 35 mph , e ) 40 mph
[EX A]: b

[EX Q]: Problem: kim finds a 4 - meter tree branch and marks it off in thirds and fifths . she then breaks the branch along all the markings and removes one piece of every distinct length . what fraction of the original branch remains ? 
Options: a ) 2 / 5 , b ) 7 / 5 , c ) 3 / 5 , d ) 8 / 15 , e ) 1 / 2
[EX A]:
c