Two of the above devices are placed in series to form a particulate removal system. Calculate the collection efficiency of this system for 12.0 μm particles. Suppose you wish to clean an aerosol stream containing unit density particles which are log-normally distributed, with dpgm = 12.0 μm, and σg = 3.0. Would the expected efficiency for these particles be greater than, equal to, or less than the efficiency specification for the mono-disperse 12.0 μm particles?