A group studied the relationship between breath rate of oxygen (Y ) and age (X ,), weight (X2), speed (X ,), heart rate at rest (X ), heart rate at run (X,) and maximum of heart rate (X 6). The data is given in the Table. Answer following questions using SAS software (see SAS demo examples ) . x2 x5 x6 44.6 44 89 11 62 178 182 45.3 40 75 62 185 185 54.3 44 85 9 45 156 168 59.6 42 68 40 166 172 49.9 38 89 55 178 180 44.8 47 44 12 58 176 176 45.7 40 75 12 70 176 180 49.4 43 81 11 64 162 176 39.4 44 81 13 64 174 180 60.1 38 82 48 170 170 1) Using adjrsq , cp, AIC options find the first three best subset regression models . Write the independent variables for each model . Adjrsq = 0.9122 (highest ) Cp = 1.7781 (lowest ) AIC = 17.0435 (lowest ) Number in Adjusted Model R -Square R -Square C(p) AIC Variables in Model 4 0.9122 0.9512 3.1835 17.1097 x1 x2 x3 x6 3 0.9112 0.9408 1.8627 17.0435 x1 x3 x6 4 0.8991 0.9440 3.6580 18.4990 x3 x4 x5 x6 4 0.8975 0.9431 3.7157 18.6556 x1 x3 x5 x6 5 0.8964 0.9540 5.0052 18.5334 x1 x2 x3 x4 x6 4 0.8947 0.9415 3.8182 18.9278 x1 x3 x4 x6 5 0.8916 0.9518 5.1448 18.9874 x1 x2 x3 x5 x6 3 0.8879 0.9252 2.8795 19.3803 x3 x4 x6 2 0.8862 0.9115 1.7781 19.0706 x3 x6