QUESTION 3 A new variable, body mass index (BMI) of the customers was introduced to the study describes in QUES'HON 2. The variable is denoted as X2 while the age of the customers is assigned as II. An analysis was performed and the following matrices were obtained. d) I")! = CC DD 12037.7 58552.43 M BB 341.36 1340.5 E FF 9844.1 360 23.2 State all the summations related to of the new varia ble. the body mass index (BMI). (2 marks) By using the matrix approach. obtain the tted regression function. Give your answer up to four decimal places. (3 marks) Construct the variance covariance matrix of b. given that the sum of squares of residual is 41211.033. Give your answer up to four decimal places. (3 marks) Determine if there is any predictor variable can be dropped from the model. Justify your answer using 5% signicance level. (6 marks) Predict at 99% confidence interval for the average claim if a customer is 52 years and her body mass index is 26. (6 marks)