What Makes Us Think That Mars Must Once Have Had

question 14

Multiple Choice

What makes us think that Mars must once have had an atmosphere that was warmer and had higher surface pressure?

• A) The atmosphere is too cold and thin for liquid water today, yet we see evidence that water flowed on the surface in the past.
• B) We think it for purely theoretical reasons, based on calculations showing that the Sun has brightened with time.
• C) The presence of inactive volcanoes on Mars tells us that there must once have been a lot of outgassing, and hence a thicker atmosphere.
• D) The fact that parts of Mars have a lot of craters tell us that Mars must once have been much warmer.

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Definitions:

Chunking

A process by which individual pieces of information are bound together into a meaningful whole, often enhancing memory retention.

Filtering

Filtering is the process of selectively focusing on certain information while ignoring other stimuli, often used in processing auditory information or in information theory.

Acoustic Encoding

The process of remembering and understanding something you hear.

Rehearsal

The cognitive process of repeatedly practicing or going over information to aid in memory retention.