"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. In estimating a 95% confidence interval estimate of the average number of days absent for the company’s workers last year what will be the standard error? should you use a z or t value in the formula? what would be the value of your UPPER limit? what is the sample proportion used in the formula?"