[EX09-026] Lunch breaks are often considered too short, and employees frequently develop a habit of “stretching” them. The manager at Giant Mart randomly identified 22 employees and observed the length of their lunch breaks (in minutes)

for one randomly selected day during the week:

30 24 38 35 27 35 23 28 28 22 26 34 29 25 28 34 24 26 28 32 29 40

a. Show evidence that the normality assumptions are satisfied.

b. Find the 95% confidence interval for “mean length of lunch breaks” at Giant Mart.