Try different forecasting methods to forecast 12 steps into the future the Turnover in the Liquor Industry in New South Wales, Australia using the *aus_retail* dataset. Try the following: MEAN, RW, TSLM(Turnover ~ trend(), TSLM(Turnover ~ trend() + season(), NAIVE, SNAIVE a) Try all of the methods and determine a best method by visual inspection of forecasts for one year. b) Now split the data into *training* and *testing* subsets of the data. Use the data until Jan 2017 as the *training* data. Using the method you have selected measure its error for forecasting the *testing* data, which is 2018 data