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 boat covers a certain distance downstream in 1 hour , while it comes back in 1 ½ hours . if the speed of the stream be 3 kmph , what is the speed of the boat in still water ? 
Options: a ) 12 kmph , b ) 13 kmph , c ) 14 kmph , d ) 15 kmph , e ) none
[EX A]: d

[EX Q]: Problem: while driving from a - ville to b - town , harriet drove at a constant speed of 105 kilometers per hour . upon arriving in b - town , harriet immediately turned and drove back to a - ville at a constant speed of 145 kilometers per hour . if the entire trip took 5 hours , how many minutes did it take harriet to drive from a - ville to b - town ? 
Options: a ) 138 , b ) 148 , c ) 150 , d ) 162 , e ) 174
[EX A]: e

[EX Q]: Problem: 15 men take 20 days of 8 hours each to do a piece of work . how many days of 6 hours each would 21 women take to do the same . if 3 women do as much work as 2 men ? 
Options: a ) 27.57 , b ) 28.57 , c ) 29.57 , d ) 30.57 , e ) 32
[EX A]:
b