how to solve (a) to get answer of 0.0102m/s

4.3 A clarifier is required to treat 15,000 m/day of wastewater for a small town. The diameter of the tank is 5.0 m with an effective water depth of 2.5 m. The tank aims to remove suspended solids of density 2,300 kg/m3. The density of the wastewater is 1,000 kg/m3 and its viscosity is 0.001 Pa.s. (a) Determine the settling velocity of a 0.12 mm diameter suspended solid particle. 0.0102 m/s (4 marks) (b) Determine if the tank is able to settle and remove suspended solids of diameter 0.12 mm and above. (3 marks) Estimate the removal efficiency of suspended solids in 4.3(b) if the wastewater flow rate is increased to 20,000 m/day. 86.5%. (1 mark)