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Part B- Problems (76 points) Q1) A specialized electronic store sells products ranging from laptops to digital cameras. One of their high selling products is 22mm lens for digital cameras. Demand for 22 mm lens in the last 8 years are as follows: Year 2017 Demand 280+10 last two digits of your student number 2018 320+10*last two digits of your student number 2019 340+10*last two digits of your student number 2020 320+10*last two digits of your student number The supply chain manager thinks that demand is stable over the years and is considering two methods to forecast the demand for 2021, i.e., (i) 2 years moving average (ii) 2 years weighted moving average with weights (0.6,0.4) and (iii) exponential smoothing with smoothing constant a=0.8 to forecast the demand. For exponential smoothing methods, he would start this method with forecast for year 2017 F2017=280+10* last two digits of your student number for 2017. b) What are the forecasts for 2019, 2020 and 2021 according to 2 years moving average? (4 points) c) What are the forecasts for 2019, 2020 and 2021 according to 2 years weighted moving average? (4 points) d) What are the forecasts for 2019, 2020 and 2021 according to exponential smoothing? (6 points) e) Compare the forecasts in (b), (c) and (d) using MAD and indicate which forecasting method is the most accurate. (7 points)