Acid rain occurs when sulfur dioxide in the atmosphere is oxidized in the presence of nitrogen dioxide. Acid rain is an example of _______.
a.
a primary pollutant
b.
a secondary pollutant
c.
a tertiary pollutant
d.
none of the above
a.
a primary pollutant
b.
a secondary pollutant
c.
a tertiary pollutant
d.
none of the above