A water treatment plant with an average flow of Q=1.2m3/s treats its water with alum at a dose of 18mg/L. Alum coagulation is used to remove particulate matter, reduce the concentration of organic matter, and reduce the alkalinity of the water according to Equation 10-1. If the organic matter concentration is reduced from 7mg/L to 2mg/L, determine the total mass of alkalinity consumed per day. 1074kg/d1240kg/d1138kg/d1181kg/d