The Earth Has an Atmosphere Which Contains

question 21

Multiple Choice

The Earth has an atmosphere which contains ...

• A) oxygen
• B) nitrogen
• C) carbon dioxide
• D) argon
• E) all of the above

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Definitions:

HIV Spread

The transmission of the Human Immunodeficiency Virus, which can occur through unprotected sex, sharing needles, or from mother to child during birth or breastfeeding.

Research

The systematic investigation into and study of materials and sources in order to establish facts and reach new conclusions.

HIV Infections

The condition caused by the human immunodeficiency virus, which attacks the immune system, potentially leading to AIDS if untreated.

African American

A term used to describe Americans of African descent, with a history and culture rooted in the African diaspora and its interaction with American society.