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: maxwell leaves his home and walks toward brad ' s house at the same time that brad leaves his home and runs toward maxwell ' s house . if the distance between their homes is 72 kilometers , maxwell ' s walking speed is 6 km / h , and brad ' s running speed is 12 km / h . what is the distance traveled by maxwell when they meet in the middle ? 
Options: a ) 14 , b ) 24 , c ) 16 , d ) 18 , e ) 20
[EX A]: b

[EX Q]: Problem: two trains of equal length are running on parallel lines in the same direction at 46 km / hr and 36 km / hr . the faster train catches and completely passes the slower train in 54 seconds . what is the length of each train ( in meters ) ? 
Options: a ) 45 , b ) 55 , c ) 65 , d ) 75 , e ) 85
[EX A]: d

[EX Q]: Problem: an seller earns an income of re 1 on the first day of his business . on every subsequent day , he earns an income which is just thrice of that made on the previous day . on the 20 th day of business , he earns an income of : 
Options: a ) 29 , b ) 57 , c ) 35 , d ) 20 , e ) 30
[EX A]:
b