In which of the following situations are you doing positive work on the box?
Throwing a box at someone.
Carrying a box in your arms across the room.
Carrying a box in your arms up the stairs.
Holding a box in your out-stretched arms, spinning around in a circle.
Catching a box that is thrown at you.
Pushing a box on the floor across the room.
Carrying a box in your arms down the stairs.
Holding a box in your arms.