The atmosphere:
A)has vertical wind speeds that are typically around one-tenth that of horizontal wind speeds.
B)is about as deep as the planet is wide.
C)is more than 99 percent contained within the first 60 miles from the earth's surface.
D)has not changed substantially in composition since the earth formed over four billion years ago.

Question

Quizplus · Accepted Answer

The majority of the Earth's atmosphere is contained within the first 60 miles (or 100 kilometers) from the planet's surface. This thin layer of gas is known as the homosphere and contains almost all of the atmosphere's mass. Beyond this height, the gases become too thin to support human life and other forms of terrestrial activity.

The Atmosphere