An experiment was conducted in order to determine if cerebral blood flow in human beings can be predicted from arterial oxygen tension (millimeters of mercury). Fifteen patients were used in the study and the following data were observed. Estimate the quadratic regression equation ? Y?x = 3o + ?1 x + 02X2.(a) Estimate the quadratic regression equation ? Y?x = ?0 + ?1x + ?2x2.(b) Test for lack of fit of the model.

Blood Flow, Arterial Oxygen Tension, x 603.40 84.33 87.80 82.20 78.21 78.44 80.01 83.53 79.46 75.22 76.58 77.90 78.80 80.67 86.60 582.50 556.20 594.60 558.90 575.20 580.10 451.20 404.00 484.00 452.40 448.40 334.80 320.30 350.30 78.20