-
Sib tsoo qws
Sib tsoo pas nrig yog siv los ua cov xov xwm sib tsoo hauv cov pas nrig mills.Thaum lub sijhawm ua haujlwm, cov txheej txheem sib tsoo tsis tu ncua ua haujlwm hauv qhov cascaded.Cov pas nrig sib tsoo ua rau cov pob zeb hauv qhov khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob.
