Question 19
The South African Climate Change and Air Quality Intergovernmental Committee monitor air quality using a Regional Pollution Index (RPI). The RPI for a particular pollutant is calculated by:
$$RPI=\frac{\text{pollutant concentration}}{\text{pollution standard level}}\times50$$
| Level | RPI |
| --- | --- |
| low | RPI between 0 and 24 |
| medium | RPI between 25 and 49 |
| high | RPI 50 or higher |
(1 point) Ozone is a pollutant. On a particular day the RPI of ozone was 85. Was the concentration of ozone less than the pollutant’s standard level? ______________________
(2 points) The standard level for the pollutant, nitrogen dioxide, is 0.12 parts per million (ppm) per hour. Scientists monitored the levels of nitrogen dioxide for one hour and determined that the RPI was 25. What was the concentration (ppm per hour) of the nitrogen dioxide? _________________________________
$$RPI=\frac{\text{pollutant concentration}}{\text{pollution standard level}}\times50$$
| Level | RPI |
| --- | --- |
| low | RPI between 0 and 24 |
| medium | RPI between 25 and 49 |
| high | RPI 50 or higher |
(1 point) Ozone is a pollutant. On a particular day the RPI of ozone was 85. Was the concentration of ozone less than the pollutant’s standard level? ______________________
(2 points) The standard level for the pollutant, nitrogen dioxide, is 0.12 parts per million (ppm) per hour. Scientists monitored the levels of nitrogen dioxide for one hour and determined that the RPI was 25. What was the concentration (ppm per hour) of the nitrogen dioxide? _________________________________