Explanation:

 1.  The ionosphere is defined as the layer of the Earth's atmosphere that is ionized by solar and cosmic radiation.  This layer also reflects radio waves back to earth.

 2.  The temperature of the troposphere generally decreases as altitude increases. The rate at which the temperature decreases, is called the environmental lapse rate .

 3.  Earth's stratospheric ozone layer, which contains about 90 percent of the ozone in the atmosphere, makes the planet habitable by absorbing harmful solar ultraviolet (UV) radiation before it reaches the planet's surface.

4.  At tropopause, fall in temperature stops.