MCQOPTIONS
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MCQOPTIONS
| 1. |
The amount of residual chlorine left in public water supply for safety against pathogenic bacteria is about |
| A. | 0.01 to 0.05 ppm |
| B. | 0.05 to 0.5 ppm |
| C. | 0.5 to 1.0 ppm |
| D. | 1.0 to 5.0 ppm |
| Answer» C. 0.5 to 1.0 ppm | |