A 100 kmol/h mixture containing 40 mol% ethanol and rest is water is fed to a distillation column equipped with a total condenser and partial reboiler. Thirty percent of the feed is vaporized before it enters the column. The distillate composition should be 85 mol% ethanol and the bottoms 98% water. The column operates at 1 atm pressure. Determine the following:

1. The flow rates of vapor and liquid in rectifying and stripping sections

2. The minimum reflux

3. The minimum number of stages

4. The actual number of stages if the column has 60% efficiency.

5. Heat duties of condenser and reboiler