Use the drop-down menus to complete each sentence about the layers of the atmosphere. If the
did not exist, Earth might be destroyed by chunks of rock from space.

The
is located 12 to 50 kilometers from Earth’s surface.

Both the
get colder as altitude increases.

The ozone in the
protects people from ultraviolet (UV) radiation.

The
has the highest temperature of any layer in Earth’s atmosphere.