Astream consisting of 44.6 mole% benzene and 55.4% toluene is fed at a constant rate to a process unit that produces two product streams, one a vapor and the other a liquid. the vapor flow rate is initially zero and asymptotically approaches half of the molar flow rate of the feed stream. throughout this entire period, no material accumulates in the unit. when the vapor flow rate has become constant, the liquid is analyzed and found to be 28.0 mole% benzene.

a manufacturer of printed circuit boards uses exponential smoothing with trend to forecast monthly demand of its product. at the end of december, the company wishes to forecast sales for january. the estimate of trend through november has been 200 additional boards sold per month. average sales have been around 1000 units per month. the demand for december was 1100 units. the company uses α = 0.20 and β = 0.10. make a forecast including trend for the month of january.

answer; rapid growth in buyer demand and high buyer switching cost;