| 1 | The air is loaded with dirt. | |
| 2 | The rain will settle the dust. | |
| 3 | A filter traps dust from the air. | |
| 4 | The dust particles collide with each other and form into larger particles. | |
| 5 | Of this material, about a percent or less was in the form of dust. |
Copyright © Purple Culture Co., Ltd. 2001 - 2026. All right reserved.
