7. Which of the following human activities has a significant contribution to the greenhouse gases of the Earth?
A. Burning coals.
B. Burning forests.
C. Burning fossil fuels in their vehicles.
D. Using materials that contain chlorofluorocarbons.

8. Which of the following phenomena will happen if too many greenhouse gases block heat in the atmodphere?
A. Global warming
B. Ice Age
C. Thunderstorm
D. Tropical storm

9. Which will happen if the Earth continues its warming?
A. drought
B. lower sea levels
C. melting polar ice caps
D. more reflected sunlight off the ice pack

10. Which of the following could you do to help decrease the effects of global warming?
A. Keep your freezer door open.
B. Keep your air conditioner on high.
C. Burn dry keaves and plastics in your backyard.
D. Turn off your lights when your not using them.


Please help me po, thank you in advance^ω^​