The following table shows a time series over 8 periods, where Y(t) are the original data observations of the series in each period. The F(t) values in the bottom row are from an exponential smoothing process calibrated with F(1) = Y(1), and an unknown smoothing constant = a. Period Y(t) F(t) 1 2 3 23 17 10 23.000 23.000 19.400 4 21 13.760 5 15 18.104 Using this information, derive the value of a and calculate F(8). 6 12 7 22 8