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Question 2 The weights (in kg) of a sample of 13 customers in a physical center are shown as follows: 95, 73, 83, 64, 58, 48, 53, 49, 68, 65, 57, 70, 72 (a) Find the following statistical measurements (i) range; (ii) median; (iii) mean; (iv) standard deviation; (6 marks) (b) If the optimum weight is defined as one standard deviation less than the mean, find the optimum weight based on this sample's data. (2 marks) (c) If one customer is randomly selected from this sample, what is the probability that the selected customer's weight is below the optimum weight as in part (b). (2 marks) (Total: 10 marks)