1) Gaseous pollutants a) Smoke b) Carbonmonoxide 2) Solid pollutants a) Dust b) Oxides of nitrogen 3) Impurities in the air are a) Pollutants b) Polluted air 4) Effects of ultraviolet rays a) Skin disease b) Indigestion 5) Green house gas is a) Carbondioxide b) Sulfur dioxide

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