How do you determine the height of a wave?

Wave height is the vertical distance between the crest (peak) and the trough of a wave. Some other definitions: Still-Water Line is the level of the lake surface if it were perfectly calm and flat. Crest is the highest point on the wave above the still-water line.

Explanation:

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.