Identify the formula used to calculate the root mean square error over a range of forecasted values, if the actual value of the time series at time t and the forecast value for time t are denoted by At and Ft respectively. 71 A-F RMSE = t-1 RMSE= 22 71 -F RMSE = (AL-FO 1-1 M= | A + Ft RMSE = 1-1 22