1. In a study investigating the relationship between noise exposure and hypertension. The following data are representative of those reported in the article. (20 points) 2. y101251462 x 60 63 65 70 70 70 80 90 80 80 y5468457976 85 89 90 90 90 90 94 100 100 100 a) Draw a scatter diagram of y (blood pressure rise in millimeters of mercury) versus x (sound pressure level in decibels). Does a simple linear regression model seem reasonable in this situation? (5 points) b) Fit the simple linear regression model using least squares. Find an estimate of . (10 points) c) Find the predicted mean rise in blood pressure level associated with a sound pressure level of 85 decibels. (5 points) Consider the data above on y = blood pressure rise and x = sound pressure level. (30 points) a) Test for significance of regression using a = 0.05. What is the P-value for this test? (10 points) b) Estimate the standard errors of the slope and intercept. (10 points) c) Test Ho: Bo = 0 versus H: o #0 using a = 0.05. Find the P-value for this test. (10 points) 3. Using above data on y = blood pressure rise and x = sound pressure level. Find a 95% confidence interval on each of the following (20 points): 4. a) 1 (5 points) b) Bo (5 points) c) Mean blood pressure rise when the sound pressure level is 85 decibels (5 points) d) Find a 95% prediction interval on blood pressure rise when the sound pressure level is 85 decibels. (5 points) Using data on blood pressure rise y and sound pressure level x. (20 points) a) What proportion of total variability in blood pressure rise is accounted for by sound pressure level? (10 points) b) Plot residuals versus and versus x. Comment on these plots. (10 points)