Plants, Trees, and Soils Naturally Emit Carbon Dioxide (CO₂) That

question 76

Multiple Choice

Plants, trees, and soils naturally emit carbon dioxide (CO₂) that enters the atmosphere. To form a benchmark level for this greenhouse gas, we can determine the amount of CO₂ that would end up in the atmosphere if there were no human activity on the planet. Suppose naturally occurring CO₂ emissions are 5 million tons per year, the social discount rate is 5%, and the stock dissipation rate is 2%. What is the eventual level of CO₂ in the atmosphere if these natural emissions continue at this rate forever?

• A) 100 million tons
• B) 250 million tons
• C) 25 million tons
• D) We do not have enough information to answer this question.

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Definitions:

Opponent-Process Theory

A psychological and neurological model that explains how the perception of colors derives from the opposition of three pairs of colors.

Color Vision

the ability of the human visual system to differentiate and perceive colors, which is produced by the interaction of light with the cone cells in the retina.

Pinna

The visible part of the ear.

Outermost Part

The most external or superficial layer of an object or body.