In a recent Indian Premier League season, the population standard deviation of the deliveries faced to score fifty runs for all batsmen was 6.37. The deliveries per fifty of 10 randomly selected batsmen are listed. Assume the deliveries per fifty are normally distributed.

Use the standard normal distribution or the t-distribution to construct a 95% confidence interval for the population mean. Justify your decision. If neither distribution can be used, explain why. Interpret the results.