Presently,the Annual Average of CO₂ Is About 400 Ppm,and the Concentration

question 29

Multiple Choice

Presently,the annual average of CO₂ is about 400 ppm,and the concentration is increasing by about ____ ppm per year.

• A)2
• B)5
• C)​8
• D)​12
• E)​15

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Definitions:

Antigens

Foreign substances that induce an immune response in the body, especially the production of antibodies.

Passive Immunity

Immunity acquired by the transfer of antibodies from another individual, as opposed to the body's own production of antibodies.

Active Immunity

Ability to produce antibodies due to the immune system’s response to a microorganism or a vaccine.

Cowpox

A disease caused by the cowpox virus, historically significant for its role in the development of the smallpox vaccine.