<span>The following which is not an example of work is </span>C. holding a tray in the cafeteria line because <span>if force displaces an object it should work. I think it's clear and I am pretty sure this answer will help you.</span>
Sure !
The work is (weight of the book) x (height of the desk above the floor).
The force (weight) is the result of gravity.
It was gravity that did the work.
Using q=1.60217662 E-19 C we get:

Then using 9.10938356E-31 kg as the mass, we get
Answer:
60 kg
Explanation:
The man's weight is equal to the weight of the water he displaces.
mg = ρVg
m = ρV
m = (1000 kg/m³) (3 m × 2 m × 0.01 m)
m = 60 kg
The man's mass is 60 kg.
C the milk carton has inertia
Inertia is an object not wanting to start moving when it's staying still, so the milk carton won't want to move and won't topple over