A random sample of 35 individuals in the waiting line for service by a bank officer is selected. From the sample, we found that the mean waiting time was 22 minutes with a standard deviation of 8 minutes. The bank officer wants to estimate the mean waiting time. i) Define the population parameter of interest in this problem. ii) Calculate the margin of error for a 90% confidence interval. iii) Using a 90% confidence level, estimate the population mean waiting time for all individuals waiting in the service line.

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