Which of the gas present in air is required for the synthesis of proteins in plants ?

1. Oxygen
2. Nitrogen
3. Ozone
4. Carbon dioxide

Which component of air controls the climatic conditions?

1. Inert gases
2. Oxygen
3. Water vapour
4. Nitrogen

Name the gas used in:

(a) weather balloons

(b) traffic lights

(c) electric bulbs

State the full forms of LPG and CNG.