Answer:
#1. Earth Has Had Three Atmospheres.
#2. Oxygen Caused the First Major Extinction
#3. The Sky Should Be Violet
#4. The Atmosphere Extends 6,200 Miles into Space
#5. It Protects Us from Meteors
#6. There are five layers within the atmosphere
#7. The atmosphere surrounds the planet, protecting it by absorbing the ultraviolet radiation from the sun, and regulating the temperature extremes that would otherwise occur between day and night.
#8. The troposphere lies closest to the Earth and is about 11 miles thick
#9. Blood Boils After 60,000 Feet into the atmoshpere