Craters on Mars Have Flatter Bottoms and Their Rims Appear

question 10

Multiple Choice

Craters on Mars have flatter bottoms and their rims appear to be more worn down than those on either Earth's Moon or Mercury. What has caused this wear?

• A) breakdown of the rocks by the extreme temperature variations between day and night
• B) erosion by the seasonal fall and subsequent melting of carbon dioxide snow
• C) erosion by wind and infilling by dust storms
• D) erosion by rainfall, now and in the past

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Definitions:

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A significantly above average level of cognitive capability, including the abilities to learn, understand, reason, and solve problems effectively.

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The passing on of physical or mental characteristics genetically from one generation to another.

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Twins who are born at the same time but develop from two different eggs fertilized by two different sperm, sharing about 50% of their DNA, similar to typical siblings.