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Question 3 (20) (Assesses probability, confidence intervals, and inferential statistics concepts.) 3.1 Assume that the revenue for Branch C follows a normal distribution with a mean of R535,000 and a standard deviation of R15,000. What percentage of months had revenue above R550,000 based on the empirical rule? (4 marks) e Ifthe probability of revenue exceeding R550,000 is 0.20, calculate the Z-score and interpret the result. (4 marks) 3.2 The company wants to predict future customer footfall based on previous trends. Calculate the probability that a randomly chosen month had footfall exceeding 36,000 customers, assuming a normal distribution (mean = 36,000, standard deviation = 2,000). (4) Why is sampling important when making predictions for future months? (3) e Discuss how confidence intervals could help XYZ Superstores estimate next month's expected footfall with 95% certainty