Suppose that a sample of 40 employees at an IT department of a large company were surveyed and asked how many hours a week they thought the company wasted on unnecessary meetings. The mean number of hours these employees stated was 11.17 and standard deviation of 3.90. Construct a 98% confidence interval to estimate the mean amount of time all employees at this department of the company believe is wasted on unnecessary meetings each week. Assume that the values are approximately normally distributed and use the t distribution. (a) What is df (degrees of freedom} in this case? df = I For part (b), round your answer to 3 decimal places. b Find t9 = 2.426 . , 2 C] - For part (c), round your answers to 2 decimal places. (c) What is the 98% confidence interval for the true average sales value for prescriptions issued by an IT