A secondary sedimentation tank receiving the effluent from an aeration tank has been monitored over a long time. Average values of input and output flows and suspended solids (SS) concentrations are given below. Calculate SS concentration and underflow from the bottom of the tank. The inflow of the sedimentation tank is 1000m3 /d and the outflow is 600m3 /d SS concentration in the influent is 3000g/m3 and SS concentration in the effluent is 30g/m3