Answer: Located within the thermosphere, the ionosphere is made of electrically charged gas particles (ionized). The ionosphere extends from 37 to 190 miles (60-300 km) above the earth's surface. It is divided into three regions or layers; the F-Region, E-Layer, and D-Layer.
Explanation:
The axons of the retina culminate in the optic nerve which forms a blind spot on the retina.
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