1. What is the atmosphere?

2. Which of the following best describes the Earth's atmosphere?

3. What is the ozone layer?

4. What two elements make up the majority of the Earth's atmosphere?

5. What layer of the Earth's atmosphere is where most meteors burn up upon entry?

6. What layer of the Earth's atmosphere is the outermost layer and where the atmosphere is the thinnest?

7. What layer of the Earth's atmosphere is the layer next to the Earth?

8. What layer of the Earth's atmosphere is heated by the Sun hitting the ozone layer?

9. What layer of the Earth's atmosphere has a very thin atmosphere, but can also become very hot?

10. In what layer of the Earth's atmosphere do planes usually fly?