3. A mixture of acetone and ethanol is fed to a column that has a side stream liquid withdrawal. The feed is 100mol/min,0.6 acetone and saturated vapor. The liquid side product withdrawn is S=15.0mols/min, liquid and from the second stage below total condenser. There is no reboiler, the liquid that is coming down at the bottom of the column is withdrawn as B. xD is 0.9, L/D is 3.5. What is the mol fraction acetone xS ? Calculate the number of stages