Question: During the month of December, a sample of 75 Hallmark patrons in Jacksonville revealed a mean amount spent of $21.90 with a standard deviation of $6.22. Of the 75 patrons, 60 were women.

a) Set up a 95% confidence interval of the true population mean amount spent in Jacksonville Hallmark stores in December.

b) Set up a 90% confidence interval of the true population proportion of the December customers at Jacksonville Hallmarks who are women.

c) If the Hallmark regional manager were interested in conducting a customer satisfaction survey, what sample size is needed if she wanted to be 95% confident of estimating the proportion satisfied with a margin of error of .035?

d) If she wanted to estimate the true mean amount spent in her Jacksonville stores within $2.00 and the standard deviation is assumed to be $10.00, how large a sample size would she need? (Use a 95% confidence interval.)