According to Newton's first law of motion, what is required to make an object slow down? (PLEASE HURRY I NEED THE ANSWER!!!)

According to newton's first law of motion, friction is  required to make an object slow down. It is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. It opposes the force being applied in an object. Hope this answers the question.

c because the action was the roller coaster reaches bottom of hill (action) reaction would be blood tends to drain away from head

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