The photochemical smog does not generally contain.

Which of the following is not a component of photochemical smog?

$CFCl_3$ is responsible for the decomposition of ozone to oxygen. Which of the following reacts with ozone to form oxygen?

Which one of the following statements is $NOT$ correct?

Match the following:
| List-$I$ | List-$II$ |
| :--- | :--- |
| $A$. Methemoglobinemia | $I$. $1 \ ppm$ of dissolved oxygen in water |
| $B$. Kidney damage | $II$. $1000 \ ppb$ of lead in drinking water |
| $C$. Bones and teeth damage | $III$. $BOD$ of drinking water is $2 \ ppm$ |
| $D$. Growth of fish is stopped | $IV$. $2000 \ ppm$ of nitrates in drinking water |
| | $V$. $50 \ ppm$ of fluoride in drinking water |

The regions of the atmosphere,where clouds form and where we live,respectively,are