Question

What does a model of the carbon cycle show? (1 point)
• The amount of Earth's carbon decreases.
• The amount of Earth's carbon increases.
• The amount of Earth's carbon is constant.
• The amount of Earth's carbon cannot be determined.

Answer 1

A model of the carbon cycle typically shows that the amount of Earth's carbon is constant. This is because carbon is continuously cycled through various processes such as photosynthesis, respiration, decomposition, and fossil fuel combustion, maintaining a balance in the total amount of carbon on Earth. So the correct answer is:

• The amount of Earth's carbon is constant.