Q15) Air is an important inexhaustible natural resource. It is essential for the survival of human beings, microbes, plants and animals. The following table shows the percentage of various gases in air.
| Contents of air | Percentage (by volume) |
|---|---|
| Nitrogen | 78 |
| Oxygen | 21 |
| Other (carbon dioxide, inert gases, water vapours, etc) | 1 |