(a) The Big Shop recently has carried out a report showing the total number of visitors to the factory. The figure is as follows: Year Q1 Q2 Q3 Q4 1 23 33 28 74 2 48 27 38 85 3 49 53 58 94 4 109 152 160 188 i) Find the seasonal variations using trend method of an additive model. (12 marks) ii) Estimate the number of tourists for the fifth year Q3. (8 marks)