How Do Scientists Estimate the Atmospheric Levels of Carbon Dioxide

question 45

Multiple Choice

How do scientists estimate the atmospheric levels of carbon dioxide that existed on Earth hundreds or thousands of years ago?

• A) They deduce it from the carbon dioxide content of fossil fuels.
• B) They measure it from bubbles of gas trapped in Antarctic ice.
• C) They estimate it from the relative numbers of carbon-based life forms that existed over time.
• D) They measure it from erupting volcanoes, bubbling hot springs, and seeping hydrothermal vents.

---

Definitions:

Muscles

Tissues in the body that have the ability to contract, thus enabling movement and force exertion.

Board Game

A physical or digital game played on a board, often involving strategy, skill, or chance with pieces or cards.

Action Figure

An action figure is a posable character toy, often based on fictional characters from movies, comics, or video games, designed for play and collection.

Parallel Play

A stage of child development in which children play adjacent to each other but do not interact or play together directly.