The Amount of Carbon Dioxide in the Atmosphere Has Increased

question 25

Multiple Choice

The amount of carbon dioxide in the atmosphere has increased by approximately___ percent since 1990.

• A) 5
• B) 15
• C) 25
• D) 50
• E) 100

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Definitions:

Autotrophs

Organisms that produce their own food from inorganic substances using light or chemical energy, such as plants and some bacteria.

Pigment

Substances that give color to living organisms, such as chlorophyll in plants or melanin in human skin.

Light

Light is electromagnetic radiation within a portion of the electromagnetic spectrum that can be perceived by the human eye, responsible for the sense of sight.

Chemical Energy

Energy stored in the bonds of chemical compounds and released in a chemical reaction, often producing heat as a by-product.