Water temperature is a factor of coagulation and flocculation. The coagulation efficiency decreases at low water temperature, because:(1) hydrolysis of inorganic salt coagulants is an _________ __ (choose endothermic/exothermic) process;(2) strength of Brownian motion of impurities ________ __ (choose increases/decreases);(3) hydration of colloids _________ __ (choose increases/decreases).