An engineer is tasked to design a separation system containing two distillation columns in series in order to produce the final product of glycerol with 90wt% purity. The first distillation column separates a 100kg/h feed of liquid mixture containing 40wt% water, 50wt% glycerol and the balance sugar to an overhead product containing 90wt% water and- no sugar. The overhead product of the first distillation column contains 98% of water in the feed to the first distillation column. Then, the bottom product of the first distillation column is fed to the second distillation column. It is given that 70% of glycerol in the feed to the second distillation column is recovered in the overhead product of the second distillation column. The overhead product of the second distillation column contains 90wt% glycerol and the balance sugar. a. Draw and label the flowchart of the process unit by indicating all input and output process variable. Perform the degree of freedom (DOF) analysis