3.1 Find the migration velocity for an existing electrostatic precipitator (ESP), which the collection plate area is 120m2, gas flow rate is 2.5m3/s, and collection efficiency is 99.5% ? (5) Hint: Use the Deutsch-Anderson equation. 3.2 Estimate the collecting plate area required for an ESP that is applied for removing fly ash in the gas stream emitted from a utility power plant. (5) Assuming that: (1) the designed collection efficiency is 99.5%, (2) the volumetric gas flow rate is 9,600m3/min (3) the resistivity of fly ash is 8109cm, and (4) the migration velocity w=7.2m/min. 3.3 Find the collection efficiency of a horizontal-flow, single-stage electrostatic precipitator consisting of two sections formed by plates 3.0m wide and 6.0m high on 25-cm centres, handling a gas flow of 2.5m3/s. Assume that the migration velocity is 12cm/s