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Assume that the demand is updated each period by Winters' trend-seasonal method. The smoothing constants are a = 0.2, B = 0.1, y = 0.2. There are T = 7 equally long periods during a year. Assume further that the last update took place at the end of period 13 and resulted as follows js = 5, 613 = 1 F, = g = 1.4, F, = F10 = u1 = 1, F12 = F3 = 0.6 The observed demand in period 14 is 3. Carry out the update and determine the forecast for period 17. Assume that the demand is updated each period by Winters' trend-seasonal method. The smoothing constants are a = 0.2, B = 0.1, y = 0.2. There are T = 7 equally long periods during a year. Assume further that the last update took place at the end of period 13 and resulted as follows js = 5, 613 = 1 F, = g = 1.4, F, = F10 = u1 = 1, F12 = F3 = 0.6 The observed demand in period 14 is 3. Carry out the update and determine the forecast for period 17