Please answer the question fully.

Question 3: a) What are the categories of forecasting techniques? Generally, how do they differ from each other? b) Monthly demand (in thousands) for component parts is as follows: First Year Second Year WN Month 1 2 3 4 5 Demand 12 11 11 8 10 Month 1 2 3 4 5 6 7 8 9 10 11 12 Demand 10 8 7 4 5 9 12 19 25 29 19 15 17 6 7 8 9 10 22 27 32 33 21 11 12 19 i) ii) Plot these observations. Estimate the best methods of forecasting future demands