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Question

Carbon dioxide enters the atmosphere through each of the following processes except one. Which one?
A. burning fossil fuels
B. volcanic eruptions
C. photosynthesis
D. respiration
A farmer has concerns about the nitrogen levels in her soil. What can she do to ensure that the nitrogen bacteria are replenished in the soil?
A. Plant a crop of mushrooms to speed up decomposition.
B. Plant a crop of legumes, such as clover or alfalfa.
C. Plant more plants to increase transpiration.
D. Clear cut the area surrounding the field.
Where is the largest reservoir of carbon on earth located?
A. in the oceans
B. in freshwater
C. on land
D. in the atmosphere
Marine organisms have carbon in their bodies in which of the following forms?
A. carbon dioxide
B. pure carbon
C. calcium carbonate
D. bicarbonate

Answer 1

1 C. Photosynthesis takes carbon dioxide out of the air in order to build glucose.

2 B. Plant a crop of legumes. Legumes make nodules on their roots where nitrogen-fixing bacteria live.

3 A. Oceans. See the table in this article. Interesting.
http://www.ldeo.columbia.edu/edu/dees/V1003/lectures/global_carbon_cycle/

4 C. calcium carbonate