QUESTION 6 1 points Save Answer A COSTCO store's monthly sales are characterized with an average of $500K and a standard deviation of $200K. Such monthly sales time series in terms of forecastability would be considered as O a. Regular O b.Lumpy O c. Trendy O d. Stable O e. Seasonal QUESTION 7 1 points Save Answer When applying a forecasting model, which measure monitors the fit of the model to detect when the model no longer accurately represents the data O a. Standard deviation of the sample O b. Variance of the sample O c. Mean squared errors (MSE) O d. Mean absolute deviation (MAD) O e. Tracking signal