The following table reports the curb weight, horsepower, and the speed at mile for 16 sports and GT cars (1998 Road & Track Sports & GT Cars).

Speed at

Sports & GT CarCurb WeightHorsepower Mile mph

Acura Integra Type R257719590.7

Acura NSX-T3066290108.0

BMW Z3 2.8284418993.2

Chevrolet Camaro z283429305103.2

Chevrolet Corvette Convertible3246345102.1

Dodge Viper RT/103319450116.2

Ford Mustang GT322722591.7

Honda Prelude Type SH304219689.7

Mercedes Benz CLK320324021593.0

Mercedes Benz SLK230302518592.3

Mitsubishi 3000GT VR-4373732099.0

Nissan 240X SE286215584.6

Pontiac Firebird Trans AM3455305103.2

Porsche Boxster282220193.2

Toyota Supra Turbo3505320105.0

Volvo C70328523697.0

COMPUTER OUTPUT - RESULTS

CAR SPEED at 1/4 mile

REGRESSION FUNCTION & ANOVA FOR MPH

MPH=74.62398-0.000806 CURBWT+0.099174 HPOWER

R-Squared=0.874119

Adjusted R-Squared=0.854753

Standard error of estimate=3.105472

Number of cases used=16

Analysis of Variance

P-value

SourceSSdfMSF ValueSig Prob

Regression870.582902435.2915045.136180.000001

Residual125.37150139.64396

Total995.9544015

CAR SPEED at 1/4 mile

REGRESSION COEFFICIENTS FOR MPH

Two-Sided

VariableCoefficientStd Errort ValueSig Prob

Constant74.623986.3429211.764930.000000

CURBWT-8.05781E-040.00233-0.345160.735491 *

HPOWER0.099170.012378.020390.000002

* indicates that the variable is marked for leaving

Standard error of estimate=3.105472

Durbin-Watson statistic=1.690434

USE THE ABOVE COMPUTER OUTPUT TO RESPOND TO THE QUESTIONS BELOW

QUESTIONS:

A stepwise multiple regression was run using the following model

MPH= b+ b(Curbwt) + b(Hpower) + e

(a)From the computer output, what is the estimated multiple regression equation?

(b)Clearly state your null and alternative hypotheses for testing the significance of both independent variables and carry out the test.What is your conclusion?

(c) Test for the significance of each individual independent variable.What is your conclusion?Which of the two independent variables should be dropped and why?

(d)Give an interpretation to the R-Squared value of the full model.

(e)The 1999 Porsche 911 has been advertised as having a curb weight of 2910 and an engine of 296 horsepower, use the full model and the final model to predict the speed at mile of this car.