Could you solve a and b step by step?

Question 4 (20 pts). A liquid mixture of 35 mole % n-hexane (H),30 mole % n-octane (O) and the balance n-decane (D) is fed to a distillation column at steady state. The bottoms product which has a flow rate of 88moles/h contains 97 mole %D and balance O.95% of D in the feed is recovered in this stream. The overhead product from this first column is fed to a second distillation column. The overhead product from the second column contains 95% of the H in the feed to this column. The composition of this stream is 93mole%H and the balance O. a) Draw the flowchart of the process and perform degrees of freedom analyses. b) Calculate all the unknown variables for the process