Question

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> What is the composition of air?

Answer 1

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Air is a mixture of different gases, water vapours and dust particles. The major components of air are as follow:
Nitogen 78%
Oxygen 21%
Water vapours and other gases < 1%