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 man rows his boat 75 km downstream and 45 km upstream , taking 2 1 / 2 hours each time . find the speed of the stream ? 
Options: a ) 6 , b ) 7 , c ) 5 , d ) 8 , e ) 9
[EX A]: a

[EX Q]: Problem: a 8000 liter tank , half - full of water is being filled from a pipe with a flow rate of 1 kiloliter every 2 minutes . at the same time , the tank is losing water from two drains at a rate of 1 kiloliter every 4 minutes and every 6 minutes . how many minutes does it take to fill the tank completely ? 
Options: a ) 8 , b ) 12 , c ) 18 , d ) 24 , e ) 48
[EX A]: e

[EX Q]: Problem: the timing of a college is from 12 p . m to 4.10 p . m . five lectures are held in the given duration and a break of 5 minutes after each lecture is given to the students . find the duration of each lecture . 
Options: a ) 52 minutes , b ) 45 minutes , c ) 46 minutes , d ) 48 minutes , e ) 44 minutes
[EX A]:
c