The force has to be in either the same or the direction to the direction of motion for work to be done. what goes in the gap?

The force has to be in either the same or the opposite direction to the direction of motion for work to be done.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

1= 26.17

2= 1.17

3=30.86

4=5.86

just took the assigment on edge