Please help me understand how to complete the last part. Thank you so much

Lenovo uses the ZX-81 chip in some of its laptop computers. The prices for the chip during the last 12 months were as follows: Month Price Per Chip Month Price Per Chip January $1.80 July $1.80 February $1.61 August $1.85 March $1.60 September $1.60 April $1.85 October $1.57 May $1.90 November $1.62 June $1.95 December $1.75 This exercise contains only part d. With a = 0.1 and the initial forecast for October of $1.79, using exponential smoothing, the forecast for periods 11 and 12 is (round your responses to two decimal places): Month Oct Nov Dec Forecast $1.79 1.76 1.75 With a = 0.3 and the initial forecast for October of $1.77, using exponential smoothing, the forecast for periods 11 and 12 is (round your responses to two decimal places): Month Oct Nov Dec Forecast $1.77 1.71 1.68 With a = 0.5 and the initial forecast for October of $1.73, using exponential smoothing, the forecast for periods 11 and 12 is (round your responses to two decimal places): Month Oct Nov Dec Forecast $1.73 1.65 1.64 Based on the months of October, November, and December, the mean absolute deviation using exponential smoothing where a = 0.1 and the initial forecast for October = $1.79 is $ (round your response to three decimal places)