The local utility company surveys 101 randomly selected customers. For each survey participant, the company collects the following: annual electric bill (in dollars) and home size (in square feet). Output from a regression analysis appears below.
Regression equation: Annual bill = 0.55 * Home size + 15
Predictor Coef SE Coef T P
Constant 15 3 5.0 0.00
Home size 0.55 0.24 2.29 0.01
What is the 99% confidence interval for the slope of the regression line?