L04 9. After plotting the following demand data, a manager has concluded that a trend-adjusted exponential smoothing model is appropriate to predict future demand. Use period 1 to 4 to estimate the initial smoothed series (use the aver- age of the first four periods) and smoothed trend (use the increase from day 1 to day 4 divided by 3). Use a = 0.5 and B = 0.4 to develop forecasts for periods 5 through 10. Period, t A, Actual 1 210 2 224 3 229 4 240 5 255 6 265 7 272 8 285 9 294 10