How would you do this on r script?

Cooling method for gas turbines. Refer to the Journal ofEngineering for Gas Turbines and Power (January 2005) study of a high-pressure inlet fog-ging method for a gas turbine engine, Exercise 5.12 (p. 280). A number of independent variables were used to predict the heat rate (kilojoules per kilowatt per hour) for each in a sample of 67 gas turbines augmented with high-pressure inlet fogging. The independent variables available are engine type (traditional, advanced, or aeroderivative), number of shafts, cycle speed (revolutions perminute), cycle pressure ratio, inlet temperature (C), exhaust gas temperature (C), air mass flow rate (kilograms per second), and horsepower (Hp units). The data are saved in the GASTURBINE file. (The first and last five observations are listed in the table above.)

(a) Use stepwise regression (with stepwise selec-tion) to find the best predictors of heat rate.

(b) Use stepwise regression (with backward elimi-nation) to find the best predictors ofheat rate.

(c) Use all-possible-regressions-selection to find the best predictors of heat rate

(d) Compare the results, parts ac. Which inde-pendent variables consistently are selected as the best predictors?

(e) Explain how you would use the results, parts ac, to develop a model for heat rate.

How would you do this on r script?

GASTURBINE (Data for first and last five gas turbines shown) RPM CPRATIO INLET-TEMP EXH-TEMP AIRFLOW 27245 9.2 1134 602 7 14000 12.2 950 446 15 17384 14.8 1149 537 11085 11.8 1024 478 27 14045 13.2 1149 553 29 HEATRATE 14622 13196 11948 11289 11964 20 18910 14.0 1066 532 8 12766 3600 35.0 1288 448 152 8714 3600 20.0 1160 456 84 9469 16000 10.6 1232 560 14 11948 14600 13.4 1077 536 12414 Source: Bhargava, R., and Meher-Homji, C. B. "Parametric analysis of existing gas turbines with inlet evaporative and overspray fogging." Journal of Engineering for Gas Turbines and Power, Vol. 127, No. 1, Jan. 2005. 20 GASTURBINE (Data for first and last five gas turbines shown) RPM CPRATIO INLET-TEMP EXH-TEMP AIRFLOW 27245 9.2 1134 602 7 14000 12.2 950 446 15 17384 14.8 1149 537 11085 11.8 1024 478 27 14045 13.2 1149 553 29 HEATRATE 14622 13196 11948 11289 11964 20 18910 14.0 1066 532 8 12766 3600 35.0 1288 448 152 8714 3600 20.0 1160 456 84 9469 16000 10.6 1232 560 14 11948 14600 13.4 1077 536 12414 Source: Bhargava, R., and Meher-Homji, C. B. "Parametric analysis of existing gas turbines with inlet evaporative and overspray fogging." Journal of Engineering for Gas Turbines and Power, Vol. 127, No. 1, Jan. 2005. 20