Represents newtons First Law for every force their is an equal and opposite reforce. Or stated more commonly for every action there is an equal and opposite reaction. The rockets burners push down on the air and in turn the air pushes back up on the rocket.
2. Represents Newton's first law (I think this one could be one or three) objects at rest remain at rest unless unless acted on by an outside force. The boy is the outside force rolling the ball up the hill.
