the Benzene-Toluene mixture containing 42% (mol) Benzene will be separated in a multi-tray/rack separator. A partial this distillation column with a condenser and a boiler contains 70% (mol) Benzene and 10% in the other part (mol) is used to ensure separation in such a way that it becomes benzene. a) How many actual (physical) trays/shelves are needed in the column. b) When the feed is delivered to the column as 75% saturated vapor and 25% saturated liquid, the