Which one of the following forces is a contact force force of gravity or force of friction​

a force of friction would be like something moving that suddenly stops because of the texture of another object while a force of gravity would be something falling and gravity pulling it down :) hope this helps

Explanation:

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the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.