Refer to the Journal of Engineering for Gas Turbines and Power (Jan. 2005) study of a high-pressure inlet fogging method for a gas turbine engine. Exercise 12.19. Consider a model for heat rate (kilojoules per kilowatt per hour) of a gas turbine as a function of cycle speed (revolutions per minute) and cycle pressure ratio. The data are saved in the file.
a. Write a complete second-order model for heat rate (y).
b. Give the null and alternative hypotheses for determining whether the curvature terms in the complete second-order model are statistically useful for predicting heat rate (y).
c. For the test in part b, identify the complete and reduced model.
d. Portions of the Minitab printouts for the two models are shown below. Find the values of SSER, SSEC, and MSEC on the printouts.
e. Compute the value of the test statistics for the test of part b.
f. Find the rejection region for the test of part b using a = .10.
g. State the conclusion of the test in the words of the problem.

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Complete Model The regression equation is HEATRATE 15583+ 0.078 RPM523 CPRATIO 0.00445 RPH CPR-0.000000 RPHSO +8.84 CPRSQ S 563 . 5 13 R-Sq 88.5% R-Sq (adj) 87.5% - # . Analysis of Variance Source Regression Residual Error 61 193 70350317547 Total DF MS 5 14852 6859 29705372 93.55 0.000 66 167897208 Reduced Model The regression equation is HEATRATE = 1206S + 0.170 RPM- 146 CPRATIO 0.002 42 RPH CPR S. 633.842 R-Sq 84.9% R-Sq (adj) 84.2 # nalysis ot Variance Source Regression Residual Error 63 25310639 Total DF MS 3 142586570 7528857 118.30 0.000 401756 66 167897208