The Average Geothermal Gradient near Earth's Surface Is

question 24

Multiple Choice

The average geothermal gradient near Earth's surface is:

• A) 100 ° C/km.
• B) 50 ° C/km.
• C) 25 ° C/km.
• D) −25 ° C/km.
• E) −50 ° C/km.

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Definitions:

Müller-Lyer Illusion

A visual illusion in which two lines of the same length appear to be of different lengths because of the addition of inward or outward facing wings at the ends of the lines.

Poggendorf Illusion

A visual illusion that involves the misperception of the position of one part of a transversal line that has been interrupted by the contour of an intervening structure.

Ponzo Illusion

A visual illusion where the context causes an object to appear larger or smaller than it actually is.

Moon Illusion

A perceptual phenomenon where the moon appears larger near the horizon than it does higher up in the sky.