Answer: C and D
Explanation:
B is talking about cells, so it's not relevant
A has nothing to do with this at all honestly
So C and D are the right answers
There are around 350,000-600,000
The skin acts as a barrier for protecting the body from the harmful things such as sun rays, moisture, cold.
<u>Explanation:</u>
Skin plays an important role in regulating body temperature. It helps to prevent harmful substances enter into our body, and does not allow to loss water in our body. Its form the barrier that prevents harmful substances and microorganisms enter in our body.
Our skin is the protecting layers and against loss of water and blood from our body. Its help us to maintain the constant body temperature. The important role of the skin us to protect our body from the ultraviolet rays.
They lower the average density of their body; because of the air it feels like a slight decrease in the weight.
B. I think I'm not so sure but that's my best guess.