Given the following data, develop a demand forecast for period 7 using a 4-period weighted moving average, with weights of 0.10, 0.15, 0.30, and 0.45, where 0.45 is used for the most recent week. Period Demand 1 2 3 4 5 6 7 11 5 12 15 9 The forecast for period 7 using the 4-period weighted moving average is 9 (enter your response rounded to two decimal places).