We Know That Carbon Dioxide Levels Were in the Atmosphere

question 3

Multiple Choice

We know that carbon dioxide levels were in the atmosphere millions of years ago through ____.

• A) radioisotope dating
• B) measuring carbon dioxide levels in fossil fuel samples
• C) measuring carbon isotope ratios in fossil fuel samples
• D) measuring carbon dioxide levels in air pockets in ice cores
• E) measuring carbon isotope ratios in air pockets in ice cores

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Definitions:

Coccygeus

A small muscle located in the pelvic area, contributing to the pelvic floor structure and assisting in supporting pelvic organs.

Mastoid Process

A bony protrusion located behind the ear on the skull that contains air cells and contributes to the middle ear structure.

Longissimus Capitis

A muscle in the back of the neck and upper thoracic region that extends, bends, and rotates the head.

Splenius

A band of muscle in the back of the neck and upper thoracic region important for movements of the head and neck, such as rotation and extension.