The grade point averages GPA for 12 randomly selected college students are shown on the right Complete parts a through c below Assume the population is normally distributed a Find the sample mean Round to two decimal places as needed b Find the sample standard deviation 5 Round to two decimal places as needed c Construct a 90 confidence interval for the population mean A 90 confidence interval for the population mean is CD S 562 2 5 ON N 1 6 2 2 02 3 2 0 8 2334 1 3 2 4 27 WODN 053 4 0 3 5 3 3