Unit 4 SBS #14-20 p.361

14. Since CO2 and water vapor are both greenhouse gases, they would absorb infrared radiation, helping maintain a stable temperature. 

15. a. a. Natural process: Burning coal and removing trees in forests
          Human activity: Breathing and photosynthesis
      b. Natural process: Decomposition of plants and animals
          Human process: Fossil fuels and livestock

16. A) Lower- increase in greenhouse/atmospheric gases, higher air pressure.

      B) Higher-  decrease in greenhouse/atmospheric gases, lower air pressure.

17. On a sunny winter day, a greenhouse with transparent glass walls is warmer than a structure with dense wooden walls because infrared light cannot escape through the glass. 

18. a. 

       b. 

19. Atmospheric CO2 gas, solid calcium carbonate, natural gas and organic molecules are all chemical reservoirs of carbon atoms. 

20. The carbon atom could be part of the atmosphere as a gas as a result of photosynthesis, in the lithosphere as plant or animal waste decay, or part of the hydrosphere as limestone.