Give Reason: the velocity of the body is taken as a measure of its kinetic energy what is the answer??

the speed (or the velocity) of the body. ... Since the kinetic energy increases with the square of the speed, an object doubling its speed has four times as much kinetic energy. For example, a car traveling twice as fast as another requires four times as much distance to stop, assuming a constant braking force.

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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