Layers in earth's atmosphere are defined as region in
a.) air mixes together
b.) different types of weather occur.
c.) planes cruise due to jet stream currents

d.) the temperature of the air remains the same.

Answer: D.) The temperature of the air remains the same.

The division of Earth's atmosphere into different layers is achieved by using the temperature as the main factor. Thus, our atmosphere is divided into five disting layers: exosphere, thermosphere, mesosphere, stratosphere and troposphere.

The exosphere is the outermost layer as well as the least dense. It contains so few oxygen and hydrogen atoms that they rarely collide with each other. The troposphere is the layer closes to the Earth's surface and it contains most of our weather.

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