13 Jane, the largest shareholder of New Vision consulting company realized that her managers are working longer than their eight-hour workday preparing proposals, overseeing crucial tasks, and taking care of the paperwork, in spite of not being paid overtime. In a bid to increase the morale of managers and the overall profitability of her company, Jane devised a policy of recognizing such overtime by allowing managers to use company time as extra leave or vacation time. However, before implementing this policy, Jane instructed the human resource manager to keep records of extra time and activities performed by managers during that time in order to establish the average amount of extra time spent by managers beyond office hours. The human resource manager picked a random sample of 18 managers in order to determine the amount of extra time they work during a specific week and obtain the results shown in the table below (in hours). 6 21 17 20 7 0 8 16 29 3 8 12 11 9 21 25 15 16 Required Assume the company time is normally distributed in the population. Constructs a 95% confidence interval to estimate the average amount of extra time per week worked