Which Substance Is of Great Concern to Scientists Studying Human-Generated

question 3

Multiple Choice

Which substance is of great concern to scientists studying human-generated greenhouse gases, and is thought to increase such that the earth's climate will be irrevocably changed by 2020?

• A)chlorofluorocarbons
• B)carbon dioxide
• C)methane
• D)nitrous oxide
• E)ozone

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Definitions:

Mandatory Age

A legally established age at which individuals are required to or are no longer allowed to engage in certain activities or behaviors.

Ageism

Prejudice or discrimination against individuals based on their age, often targeting older adults.

Graying of America

Refers to the increasing proportion of the population that is elderly, a demographic trend resulting in a higher median age in the United States.

Word Puzzles

Games or problems that involve the manipulation of letters and words to solve challenges or find solutions.