What three things are need for work to be done

power, a force, and movement in the opposite direction of the applied force

Explanation:

Convection

Convection is heat transfer by mass motion of a fluid such as air or water when the heated fluid is caused to move away from the source of heat, carrying energy with it. Convection above a hot surface occurs because hot air expands, becomes less dense, and rises (see Ideal Gas Law).

Explanation:

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