17. 15 randomly selected nurses in southern California had the following salaries 6200 6500 6750 7200 5800 5950 6175 6345 5695 7350 7000 6800 6950 6695 7100 (a) Find the mean and standard deviation for sample. [Hint input the list L1 and then Calculate] ('0) Find the critical value 211/2 01' tar/2 for 90% condence interval. Draw and Label. (c) Find the margin error for this confidence interval. (d) Find the 90% confidence interval for the mean salary of all nurses in southern California