A.鋁鹽 B.有機(jī)高分子 C.二價(jià)鐵鹽 D.三價(jià)鐵鹽
A.2.0 B.2.5 C.5.0 D.1.5
A.減小終限流速,增大水舌阻力系數(shù) B.增大終限流速,增大水舌阻力系數(shù) C.減小終限流速,減小水舌阻力系數(shù) D.增大終限流速,減小水舌阻力系數(shù)