| 1 | A | B | C | D |
| --- | --- | --- | --- | --- |
| 2 | Density of air - Dry air |  |  |  |
| 3 | Temperature T (°C) | Speed of sound c (m/s) | Density of air ρ (kg/m3) | Characteristic specific acoustic impedance z0 (Pa·s/m) |
| 4 | 35 | 351.88 | 1.1455 | 403.2 |
| 5 | 30 | 349.02 | 1.1644 | 406.5 |
| 6 | 25 | 346.13 | 1.1839 | 409.4 |
| 7 | 20 | 343.21 | 1.2041 | 413.3 |
| 8 | 15 | 340.27 | 1.2250 | 416.9 |
| 9 | 10 | 337.31 | 1.2466 | 420.5 |
| 10 | 5 | 334.32 | 1.2690 | 424.3 |
| 11 | 0 | 331.30 | 1.2922 | 428.0 |
| 12 | −5 | 328.25 | 1.3163 | 432.1 |
| 13 | −10 | 325.18 | 1.3413 | 436.1 |
| 14 | −15 | 322.07 | 1.3673 | 440.3 |
| 15 | −20 | 318.94 | 1.3943 | 444.6 |
| 16 | −25 | 315.77 | 1.4224 | 449.1 |

Question: How's air like at 20 °C?
Answer: At 20 °C, dry air has a density of 1.2041 kg/m³.