Earth is approximately spherical in shape like all planets and stars. Earth is composed mostly of rock. Three-fourths of its surface is covered by a relatively thin layer of water (some of it frozen), and the entire planet is surrounded by a relatively thin blanket of air.
Answer: Integumentary.
Explanation:
The integumentary system is the system that protects the body from damage such as loss of water or abrasion from outside. For example, nails, hair, skin, etc.
No the brain is always developing as you learn or experience new things every single day.
