For incomplete separation drainage system, there is sewage drainage system but not complete rainwater drainage system A. True B. False 2. For municipal wastewater, an equalization basin tank is normally installed for pretreatment, A. True B. False 3. Coagulation effect increases with turbidity, and decreases with water temperature A True False 4 Settling time and velocity are related to the water depth in discrete particle settling for sedimentation A True False 5 Air flotation is used to remove suspended substances that can't be removed by sedimentation and natural flotation. A True B. False 6. Advantages of air flotation in water treatment process are: higher efficiency than sedimentation tank, low water content in scum, can remove several kinds of impurities. A True False Bubbles should be sufficiently dispersed. Usually, bubbles' diameters should be less than 100 um. A. True B. False x. The difference between rectangular sedimentation tank and rectangular air flotation tank is that scums of air flotation tank is discharged from the top, while sludge of sedimentation tank is discharged from the bottom A True a False In natural water, the ion exchange sequences for strong- base and weak-base anion exchange resin are the same, while the ion exchange capacities are different A True False 10 We can use weak-acid cation exchange resin to treat raw water with high concentration of Caso, Mg. A True False