One of the major measures of the quality of service provided byany organization is the speed with which it responds to customercomplaints. A large family-held department store selling furnitureand flooring, including carpet, had undergone a major expansion inthe past several years. In particular, the flooring department hadexpanded from 2 installation crews to an installation supervisor, ameasurer, and 15 installation crews. Last year, there were 50complaints concerning carpet installation. The following data, alsoin the file FURNITURE, represent the number of days between thereceipt of a complaint and the resolution of the complaint: 54 5 35137 31 27 152 2 123 81 74 27 11 19 126 110 110 29 61 35 94 31 26 512 4 165 32 29 28 29 26 25 1 14 13 13 10 5 27 4 52 30 22 36 26 2023 33 68 Problem 4 Please continue for problem questions…

a. Construct and interpret a 95% confidence interval estimate ofthe population mean number of days between the receipt of acomplaint and the resolution of the complaint and interpret. UseMinitab

b. What assumption must you make about the populationdistribution in order to construct the confidence interval estimatein (a)?

c. Do you think that the assumption needed in order to constructthe confidence interval estimate in (a) is valid? Explain.