Using the provided data set, compute the Nave, Two-period Moving Average, Three- period Moving Average, Two-period Weighted Moving Average with weights (0.6, 0.4), Three- period Weighted Moving Average with weights (0.5, 0.3, 0.2), Linear Trend, and Exponential Smoothing with alpha=0.4 and alpha=0.8 forecasts for sales.

MM-YY	Period	Sales
	t	St
Jul-09	1	3,924
Aug-09	2	2,619
Sep-09	3	6,920
Oct-09	4	5,676
Nov-09	5	8,348
Dec-09	6	6,044
Jan-10	7	6,877
Feb-10	8	6,535
Mar-10	9	6,395
Apr-10	10	6,684
May-10	11	5,414
Jun-10	12	3,180
Jul-10	13	4,350
Aug-10	14	3,175
Sep-10	15	6,935
Oct-10	16	6,356
Nov-10	17	8,919
Dec-10	18	7,146
Jan-11	19	7,763
Feb-11	20	7,397
Mar-11	21	7,286
Apr-11	22	7,498
May-11	23	6,386
Jun-11	24	4,209
Jul-11	25	4,825
Aug-11	26	3,764
Sep-11	27	7,066
Oct-11	28	7,015
Nov-11	29	9,535
Dec-11	30	8,278
Jan-12	31	8,773
Feb-12	32	8,393
Mar-12	33	8,288
Apr-12	34	8,432
May-12	35	7,455
Jun-12	36	5,346