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: if 36 men can do a piece of work in 25 hours , in how many hours will 12 men do it ? 
Options: a ) 22 , b ) 38 , c ) 60 , d ) 88 , e ) 75

SOLUTION: e

PROBLEM: Problem: difference of two parallel sides of atrapezium is 4 cm . perpendicular distance between them is 10 cm . if the area of the trapezium is 250 cm ^ 2 . find the lengths of the parallel side ? 
Options: ['a ) 20 cm and 21 cm', 'b ) 25 cm and 23 cm', 'c ) 27 cm and 23 cm', 'd ) 30 cm and 34 cm', 'e ) 28 cm and 36 cm']

SOLUTION:
c