What is CNG ? Give its one use.
From which natural substance are liquid fuels formed ?
Which gas is the main constituent of LPG ?
How was petroleum formed in nature ?
Why do green leaves not catch fire easily ?
What is CNG ? Give its one use.
From which natural substance are liquid fuels formed ?
Which gas is the main constituent of LPG ?
How was petroleum formed in nature ?
Why do green leaves not catch fire easily ?