What are the names and chemical formulas for three of the most studied pollutants (primary or secondary)?

1.       CH4 (hydrocarbons)   --  primary pollutant

2.       NO2 (nitrogen dioxide)  -- primary pollutant

3.       O3 (Ozone)  -- secondary pollutant

A primary pollutant is an air pollutant emitted directly from a source while a secondary pollutant is not directly emitted but forms when other pollutants (primary pollutants) react in the atmosphere.

the fossil record provides evidence of a common ancestor to many species.

answer; behavioral neuroscience;