What Has Changed Over the Last Century That Makes Scientists

question 46

Multiple Choice

What has changed over the last century that makes scientists believe the rise in average global temperature is not just a normal temporary fluctuation?

• A) The amount of water vapor in the atmosphere has increased.
• B) The amount of carbon dioxide in the atmosphere has increased.
• C) The amount of sunlight heating Earth has increased.
• D) The amount of heat going back out into space has increased.
• E) The amount of forested land has increased.

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Definitions:

Opportunity Cost

The cost of choosing one option over another, typically represented by the benefits that could have been gained by choosing the alternative.

Depletable Resource

A natural resource that can be diminished or exhausted by use, such as fossil fuels, minerals, or forests.

Extraction Cost

The expenses associated with the removal of raw materials from their natural setting for use or sale.

Non-Monetary Benefits

Advantages or perks associated with a job or situation that are not in the form of money, such as health insurance or flexible working hours.