2.  Nitrogen - 78%  Oxygen - 21%  Argon & Carbon Dioxide - 1%

3.  Troposphere  Stratosphere  Mesosphere  Thermosphere  Exosphere

4.  is the first layer above the surface and contains half of the Earth's atmosphere.  Weather occurs in this layer.Weather

5.  This layer extends from the top of the troposphere to a height of about 80 kilometers.  The air is much thinner in this layer.

6.  is a cold layer where the temperature generally decreases with increasing altitude.  Here in the mesosphere, the atmosphere is very rarefied nevertheless thick enough to slow down meteors hurtling into the atmosphere, where they burn up, leaving fiery trails in the night sky.

7.  The temperature is hot and may be as high as thousands of degrees as the few molecules that are present in the thermosphere receive extraordinary large amounts of energy from the Sun.

8.  This is the space where gas molecules of air are wide apart and ions and molecules are flying off into space because of lack of gravity which holds them to the atmosphere.

12.  The bases of these clouds are at an above 6,000 meters or higher.  They are composed of ice crystals & are generally clean.

13.  Cirrus  Cirrocumulus  Cirrostratus

14.  These clouds are found at heights ranging from 2,000 to 6,000 meters

15.  Altocumulus  Altostratus

16.  The bases of these clouds range from near the surface to about 2,000 meters.

17.  Stratus  Stratocumulus  Nimbostratus

18. end of my report.. Elvinia f.palino Bsba-Human resource management