Answer:
h - height
Explanation:
gravitational potential energy = m * g * h
m stands for mass. Mass doesn't change in physics
g stands for gravitational acceleration. It is a constant.
h stands for height. When the skater moves up and down the track the height from the ground changes. Therefore this variable does change.
Answer:
The oxygen in inhaled air passes across the thin lining of the air sacs and into the blood vessels. This is known as diffusion. The oxygen in the blood is then carried around the body in the bloodstream, reaching every cell. When oxygen passes into the bloodstream, carbon dioxide leaves it.
Explanation:
Answer:
a. to defend against bacteria
Explanation:The skin helps protect the body and various body cells from infection. A break in the continuity of a skin can result into harmful germs,bacteria infection penetrating into the body system. Hence the skin is a protective covering from germs,infection.
A. chemical precipitation of minerals from seawater