The hind legs of the frog are adapted for leaping and swimming. They have strong extensor muscles. When these muscles contract, the limbs extend thrusting the foot against the water or land. The frog's forelimbs are shorter and used to steer the frog while swimming and to absorb shock while landing.
Melting ice caps and glaciers
Answer:
the answer is B, The activation energy must be reached.
Explanation:
One example of stimulus is reacting to a hot pan. If you touch it, you immediately pull your fingers back. This is your nervous system sending alerts through your body, and to your muscular system. Your muscular system allows you to bend your arm, and move your fingers away from the hot pan.
:) Hope this helps!