(c)Find a 95% confidence interval for the regression coefficient of age.

3. (12 pts) A large company employs several thousand people in the manufacture of keyboards, equipment cases, and cables for the computer industry. The personnel manager of the company would like to nd ways to forecast the absentee rate among the company employees. An effective method of forecasting would greatly strengthen the ability to plan properly. He took a sample of 15 employees and recorded the number of absent days (Y) during the last scal year along with employee age (X). The computer output of a regression analysis is as follows. The regression equation is absent days = - 4.28 + 0.254 age Predictor Coef SE Coef T Constant -4.277 1.116 - 3.83 age 0.25379 0.02850 8.91 S = 1.10807 R-Sq = 85.9%