1. Welcome to... A Game of X’s and O’s

2. Another Presentation © 2000 - All rights Reserved markedamon@hotmail.com

3. 789 456 123

4. 789 456 123 Scoreboard X O Click Here if X Wins Click Here if O Wins

5. 1 78% of the Earth’s atmosphere

6. 1 Home N 2

7. 2 T.V. & Radio satellites revolve around earth in this layer

8. 2 Thermosphere

9. 3 The solid portion of the Earth

10. 3 Lithosphere

11. 4 The 4 gases that were in Earth’s 2 nd atmosphere

12. 4 N 2, H 2, CO 2, H 2 O

13. 5 layer the space shuttle revolves around Earth in

14. 5 Exosphere

15. 6 % of all Earth’s gases in the troposphere

16. 6 75%

17. 7 Earth got it’s oxygen this way

18. 7 Photosynthesis

19. 8 Volcanoes and lava gave off these three gases early on in the Earth’s development

20. 8 NH 3, CH 4, CO 2

21. 9 Meteors usually burn up before they leave this layer

22. 9 Mesosphere