Given the accompanying sample data, use Excel's formula options to find the 90% confidence interval for the population mean. Assume that the population is normally distributed and that the population standard deviation equals 5.

A1:A20 is -10, -9, -7, -7, -6, -6, -4, -4, -3, -2, -1, 1, 4, 4, 5, 6, 8, 8, 8, 10 The average of those # is -0.25

Confidence Coefficient = 0.9

Population Standard Deviation = 5 (E10)

Sample Size n = 20 (E11)

a/2 = 0.05 (E12)

I need to find out

Lower Limit of Confidence Interval compute the lower limit of confidence interval using A1:A20. E10,E11, and E12

Upper Limit Confidence Interval