A mixture of 100 kg mol that contains 60 mol % n-pentane (A) and 40 mol % nheptane (B) is vaporized at 101.32 kPa pressure under differential conditions until 40 kg mol are distilled. Use equilibrium data from Example 26.3-2. a. What is the average composition of the total vapor distilled and the composition of the remaining liquid? b. If this same vaporization is done in an equilibrium or flash distillation and 40 kg mol are distilled, what is the composition of the vapor distilled and of the remaining liquid?