MCQOPTIONS
Saved Bookmarks
| 1. |
How is sewage water purified for recycling? |
| A. | By the action of fish. |
| B. | By the action of microorganisms. |
| C. | By the action of fuels. |
| D. | By the action of non-biodegradable chemicals. |
| Answer» D. By the action of non-biodegradable chemicals. | |