A major department store chain is interested in estimating the mean amount its credit card customers spent on their first visit to thechain's new store in the mall. Fifteen credit card accounts were randomly sampled and analyzed with the results Upper X overbar

Xequals

=$50.50 and Upper S equals 20.

S=20. Construct a95% confidence interval for the mean amount thestore's credit card customers spent on their first visit to thechain's new store in the mall assuming that the amount spent follows a normal distribution.