Q. After cleaning a slow sand filter, the filtered water is not used for (Solved)
1. 6 hours to 12 hours
2. 12 hours to 18 hours
3. 18 hours to 24 hours
4. 24 hours to 36 hours
- d. 24 hours to 36 hours
1. 6 hours to 12 hours
2. 12 hours to 18 hours
3. 18 hours to 24 hours
4. 24 hours to 36 hours