TASK DEFINITION: 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'.
PROBLEM: Problem: a river boat leaves silver town and travels upstream to gold town at an average speed of 3 kilometers per hour . it returns by the same route at an average speed of 7 kilometers per hour . what is the average speed for the round - trip in kilometers per hour ? 
Options: a ) 4.2 , b ) 7.1 , c ) 7.2 , d ) 7.5 , e ) 8.0

SOLUTION: a

PROBLEM: Problem: john and lewis leave city a for city b simultaneously at 6 a . m in the morning driving in two cars at speeds of 40 mph and 60 mph respectively . as soon as lewis reaches city b , he returns back to city a along the same route and meets john on the way back . if the distance between the two cities is 240 miles , how far from city a did john and lewis meet ? 
Options: a ) 150 miles , b ) 160 miles , c ) 140 miles , d ) 170 miles , e ) 200 miles

SOLUTION: b

PROBLEM: Problem: if jack walked 8 miles in 1 hour and 15 minutes , what was his rate of walking in miles per hour ? 
Options: a ) 4 , b ) 4.5 , c ) 6 , d ) 6.4 , e ) 15

SOLUTION:
d