The Keeling Curve in Figure 25

question 108

Multiple Choice

The Keeling curve in Figure 25.1, below, shows that while CO₂ levels oscillate on an annual basis, overall CO₂ levels increase from year to year. Why has this trend continued in the last 50 years?

• A)increasing rates of aerobic respiration associated with the rise in world population
• B)decreasing rates of oxygenic photosynthesis by plants and algae
• C)clearing of forests to create agricultural land outside the tropics
• D)combustion of fossil fuels

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Definitions:

Paycuts

Reductions in the amount of money employees are paid as wages or salaries.

Mobbing

A form of bullying in which an individual is harassed or attacked by a group, often within a workplace or institutional setting.

Bullying

Involves repeated aggressive behavior with the intention to hurt another person, physically or mentally.

Workplace Bullying

Repeated, health-harming mistreatment of an employee by coworkers or superiors, including verbal abuse, threats, and other forms of intimidation.