Over the Last 150 Years CO₂ Levels in the Atmosphere

question 17

Multiple Choice

Over the last 150 years CO₂ levels in the atmosphere have

• A)increased.
• B)remained the same.
• C)decreased.
• D)increased,and then decreased.

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Definitions:

Dependent Variables

In research, these are the variables that are studied to see if they change as a result of alterations in other variables (independent variables).

Detect

To discover or identify the presence of something concealed or subtle.

Salary Negotiations

The process of discussing and agreeing on the compensation package for a job position between an employer and employee.

Treatment

A specific method or approach used in dealing with or improving a problem or medical condition.