In a stack emission measurement at an industry, the stack cross-sectional area at 30 m height was divided into four equal sectors. The measured velocities and SO
2 concentrations through these sectors at this height are given in the table.
The mean SO
2 concentration from the stack is ______ mg/m
3 (rounded off to two decimal places).
| Sector Number | Velocity (m/s) | SO2 Concentration (mg/m3) |
|---|
| 1 | 15 | 1000 |
| 2 | 17 | 1150 |
| 3 | 19 | 1250 |
| 4 | 21 | 1275 |