Results from the Mars Exploration Rovers Spirit and Opportunity Suggest

question 6

Multiple Choice

Results from the Mars Exploration Rovers Spirit and Opportunity suggest that liquid water

• A) has never existed in significant quantities on the surface of Mars
• B) was once plentiful on the surface of Mars
• C) is only present in the Tharsis region of Mars
• D) is present in large quantities beneath the Martian surface today

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Definitions:

Purity

The quality or state of being free from contamination, adulteration, or imperfection; often associated with moral or ethical cleanliness.

Wavelength

The gap between one peak of a wave and the next, particularly in sound waves or electromagnetic waves.

Subliminal

Pertaining to stimuli or psychological processes that occur below the threshold of conscious awareness.

Below Threshold

Refers to stimuli that are too weak in intensity to evoke a perceptible response or awareness.