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: calculate the speed of a boat in still water ( in km / hr ) if in one hour , the boat goes 10 km / hr downstream and 4 km / hr upstream . 
Options: a ) 7 kmph , b ) 8 kmph , c ) 9 kmph , d ) 7 kmph , e ) 6 kmph
[EX A]: a

[EX Q]: Problem: the sum of two consecutive integers is 61 . find the numbers . 
Options: a ) 17 , 18 , b ) 30,31 , c ) 5 , 6 , d ) 1 , 2 , e ) 8 , 9
[EX A]: b

[EX Q]: Problem: how long does a train 165 meters long running at the rate of 54 kmph take to cross a bridge 850 meters in length ? 
Options: a ) 28 , b ) 27 , c ) 55 , d ) 18 , e ) 67.7
[EX A]:
e