(a) Fit a linear regression models to the these data using profits as the dependent variable and sales and assets as the independent variables.

(b) Analyze the residuals to check the adequacy of the model . Compute the leverages associated with the data points. Does one (or more) of these companies stand out as an outlier in the set of independent variables data points?

(c) Generate a 95% prediction intervals for profits corresponding to sales of 100(billions of dollars) and assets of 500(billions of dollars).

(d)Carry out likelihood radio test of H0:U1=0 with a significance level of a=0.05. Should the original model be modified? Discuss.

(e)Calculate the CP and AIC for each possible regression . you chose best model of all possible regression? Explain.

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