Assume that you know that shares listed on a particular stock exchange are normally distributed with a standard deviation of $6.75. In order to estimate the mean share price on this stock exchange, a random sample of 25 shares prices was collected at the end of trading on one particular day. The sample had a mean share price of $40.16.

a) Briefly explain why this sample of 25 share prices is NOT time series data.

b) Construct a 95% confidence interval for the mean share price of stocks listed on this stock exchange.

c) Provide a practical interpretation of the interval you have constructed in b) in the context of this question.

d) If instead you had been asked to construct a 99% confidence interval in b), would the 99% interval be more or less precise than the 95% interval? Briefly explain the reasoning behind your answer (no calculation required)