The Carbon Dioxide Atmosphere of Mars Was Much Denser in Mars's

question 81

Multiple Choice

The carbon dioxide atmosphere of Mars was much denser in Mars's early history than it is now.What process is now believed to have begun this atmospheric thinning?

• A) The solar wind stripped the outer atmosphere from the planet.
• B) The light CO₂ molecules escaped directly into space because of the weak gravity of Mars.
• C) The CO₂ molecules were broken down by solar UV photons,creating the lighter molecules,CO and O₂,which then escaped into space.
• D) The CO₂ was washed out of the atmosphere by rain.

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Definitions:

Poorer Nations

countries with low levels of economic productivity, low per capita income, and generally low standards of living.

Balance

Balance refers to the state of stability and equilibrium, either physically, as in the body's ability to maintain a stable posture, or metaphorically, such as in emotional or mental stability.

Pedal

Pertaining to or operated by the foot or feet, such as bicycle pedals or the pedals of a car.

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A human-powered, pedal-driven vehicle with two wheels attached to a frame, one behind the other.