What is the largest contributor to greenhouse gases?

Related questions

1. What happened to the ozone hole?
2. What replaced CFCs used as a refrigerant?
3. What did the Montreal Protocol prohibit?
4. Do all aerosols have CFCs?
5. Does co2 destroy the ozone layer?
6. Are HFCs better than CFCs?
7. Do they still use Freon in refrigerators?
8. What is used instead of CFC?
9. What is the effect of CFC on Ozone Layer?
10. How is ozone harmful to us?

Tags

1. #states
2. #fossil
3. #united
4. #greenhouse
5. #source
6. #emissions
7. #fuels
8. #electricity
9. #activities
10. #transportation
11. #largest
12. #human
13. #burning