Valles Marineris Is a Wide, Deep Network of Chasms Stretching

question 44

Multiple Choice

Valles Marineris is a wide, deep network of chasms stretching for some 2500 miles on the surface of Mars. How do we believe such a big set of canyons formed originally?

• A) it was caused by tectonic pressures from deep within the planet
• B) it was produced suddenly by flooding water some four billion years ago
• C) it was scoured out of the Martian sands by the action of the regular dust storms
• D) it was made by hundreds of impacts from space billions of years ago
• E) the canyons were places the ancient Martians used for drag racing

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Definitions:

Expressive Vocabulary

The set of words a person can actively use in speech or writing to express their thoughts and feelings.

Cooing

Early vocalization by infants that involves the production of soft, murmuring sounds, often expressing contentment or engaging in early communication.

Cooing

The early vocalization stage in infants, characterized by the production of soft, murmuring sounds, typically starting around 6 to 8 weeks of age.

Babbling

An early stage in language development where infants produce sounds, combining vowels and consonants, that resemble speech.