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HowStuffWorks on MSNThe Worst Air Quality in the World Is in Mountainous TerrainAir pollution is widely recognized as a major threat to public health, and while air quality data is widely available, the ...
Ozone is a gas comprised of three oxygen (O3) atoms. It is unstable and reacts easily to other gases. In its natural state, it is a component in several levels of the atmosphere. At high altitudes ...
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