Smog is essentially caused by presence of?
A. O2 and N2
B. O3 and N2
C. O2 and O3
D. Oxides of Sulphur and nitrogen
Answer:D
Smog is essentially caused by presence of?
A. O2 and N2 B. O3 and N2 C. O2 and O3 D. Oxides of Sulphur and nitrogen