1B. The labor relations manager of a large corporation wished to study the absenteeism among workers at the company's central office during the last year. A random sample of 25 workers revealed the following: an average of 9.7 days; a standard deviation of 4.0 days; and 12 employees were absent more than 10 days. Set up a 95% confidence interval estimate of the proportion of workers absent more than 10 days last year