Which one of the following pollutants or pairs of pollutants is formed due to photochemical reactions?
a) CO alone
b) O₃ and PAN
c) PAN and NH3
d) NH3 and CO
Which one of the following pollutants or pairs of pollutants is formed due to photochemical reactions?
a) CO alone
b) O₃ and PAN
c) PAN and NH3
d) NH3 and CO
