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'.

[Q]: Problem: jack and jill are marathon runners . jack can finish a marathon ( 42 km ) in 3.5 hours and jill can run a marathon in 4.2 hours . what is the ratio of their average running speed ? ( jack : jill ) 
Options: a ) 14 / 15 , b ) 15 / 14 , c ) 4 / 5 , d ) 6 / 5 , e ) can not be determined
[A]: d


[Q]: Problem: a man can row 5 kmph in still water . when the river is running at 2 kmph , it takes him 1 hour to row to a place and black . what is the total distance traveled by the man ? 
Options: a ) 5.75 , b ) 5.7 , c ) 5.76 , d ) 4.2 , e ) 5.71
[A]: d


[Q]: Problem: if a car went the first third of the distance at 80 kmh , the second third at 18 kmh , and the last third at 48 kmh , what was the average speed of the car for the entire trip ? 
Options: a ) 34 kmh , b ) 40 kmh , c ) 42 kmh , d ) 44 kmh , e ) 50 kmh
[A]:
a