36. Explain why a 95% confidence interval estimate for the mean value of y at a particular x is narrower than a 95% confidence interval for an individual y value at the same value of x. 37. If 2 R =0.95 , n=11, and (Y Y )2=100, 2 what is S e ? 38. You are given the following information from fitting a multiple regression with three variables to 30 sample data points: b1=1.3 b2=10.0 b3 =25.2 S b =0.3 1 S b =2.0 Test the following hypotheses, Use =0.05 a) 1=0 b) 2=0 a) 3=0 2 S b =15.0 3