1. Perform a runs test for the sales data shown below. Does the data have a trend? Explain. Time 1 2 3 4 5 6 7 8 9 10 11 12 Sales- 83 72 87 63 61 78 125 139 124 128 133 119 2. Which of the following forecasting models is superior for predicting future sales based on the sum of squared differences criterion? a) Constant model with a constant prediction of 102 b) Last period model c) Moving average model with n= 2 d) Moving average model with n= 3 e) Weighted moving average model with n= 2, C1 = 0.6, C2 = 0.4 f) Weighted moving average model with n= 3, C1=6, C2 = 4, C3 = 2 g) Exponentially weighted moving average model with xo = 76 and a = 0.35 h) Exponentially weighted moving average model with xo = 76 and a = 0.7