The monthly incomes for

12

randomly selected people, each with a bachelor's degree in economics, are shown on the right. Complete parts (a) through (c) below.

Assume the population is normally distributed.

4450.89	4596.68	4366.43
4455.51	4151.88	3727.74
4283.18	4527.63	4407.52
3946.55	4023.26	4221.37

Question content area bottom

Part 1

(a) Find the sample mean.

x=enter your response here

(Round to one decimal place as needed.)

Part 2

(b) Find the sample standard deviation.

s=enter your response here

(Round to one decimal place as needed.)

Part 3

(c) Construct a

99%

confidence interval for the population mean

.