A recent 10-year study conducted by a research team at the Great Falls Medical School was conducted to assess how age, symbolic blood pressure, and smoking relate to the risk of strokes. Risk is interpreted as the probability (times 100) that the patient will have a stroke over the next 10-year period. For the smoking variable, define a dummy variable with 1 indicating a smoker and 0 indicating a nonsmoker. (a) Develop an estimated multiple regression equation that predicts the risk of a stroke given the person's age, systolic blood pressure, and whether the person is a smoker. (b) Is smoking a significant factor in the risk of a stroke> Use a 0.05 level of significance. (c) What is the probability of a stroke over the next 10 years for Art Speen, a 68-year-old smoker who has systolic blood pressure of 175?

Risk Age Blood Pressure Smoker N 12 57 152 No W 24 67 163 No 4 13 58 155 No UI 56 86 177 Yes 28 59 196 No 51 76 189 Yes OO 18 56 155 Yes 31 78 120 No 0 37 80 135 Yes 11 15 78 98 No 12 22 71 152 No 13 36 70 173 Yes 4 15 67 135 Yes 15 48 77 209 Yes 6 15 60 199 No 7 36 82 119 Yes 8 8 66 166 No 9 34 80 125 Yes 20 3 62 117 No 21 37 59 207 Yes 22 23