Refer to the IHS Journal of Hydraulic Engineering (September 2012) study of water pipes susceptible to breakage, Exercises 11.21 and 11.37. Recall that civil engineers used simple linear regression to model the ratio of repair to replacement cost of commercial pipe (y) as a function of the diameter (x, in millimeters) of the pipe. The Minitab printout of the analysis is reproduced on the next page. Are the engineers able to conclude (at α = .05) that the cost ratio increases linearly with pipe diameter? If so, provide a 95% confidence interval for the increase in cost ratio for every 1-millimeter increase in pipediameter. (This interval is shown on the printout.)

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Madel parameters: Pr> It 11.9148 <0,0001 Lower bound (95K) Upper bound (95%) 8086.7957 -254.1249 Standard error 829.0411 41.9014 Value 9877.8300 Source Intercept 11668.8643 -3.9045 SEARCHFR -163.6024 0.0018 -73.0799 Equation of the model: CATCH = 9877.82997-163.60242*SEARCHFREQ Hodel mary R-sq R-ag (adj) PRESS R-ag ipred) 92.094 0.221034 95.2EN 4.83 3.197108 Coefticients Coet BE Coe! 6.670 -Value -Value Sem Constant DIANETER 0.004786 0.000122 10.004077, 0.00s494) VIF 0.121 4.412, 55.a 0.0০০ 6.144) 14.07 0.000 1.00 Begrension Equatioe NATIO 6.670 D.004794 DIANETER