Answer:
By contracting, muscles pull on bones and allow the body to move. When you want to bend your elbow, your biceps muscle contracts, and, at the same time, the triceps muscle relaxes. The biceps is the flexor, and the triceps is the extensor of your elbow joint.
Explanation:
yeah, hope it helps a little. :)
The protons! Is it the answer
For the very last question you would first divide 8,900 by 12 and the number you get will be the answer. You should get 741.66