Consider a regression situation in which y = hardness of molded plastic and x = amount of time elapsed since termination of the molding process. summary quantities included the following. n = 14 b = 3.00 ssresid = 1233.420 sum (x - x^^\_)^2 = 4023.16

(a) calculate the estimated standard deviation of the statistic b. (give the answers to four decimal places.)
(b) obtain a 95% confidence interval for β, the slope of the true regression line. (give the answers to two decimal places.)