Refer to the U.S. Army Corps of Engineers data on fish contaminated from the toxic discharges of a chemical plant located on the banks of the Tennessee River in Alabama, presented in Exercise. In that exercise, you fitted the first-order model E(y) = β0 + β1x1 + β2x2 + β3x3, where y = DDT level in captured fish, x1 = miles captured upstream, x2 = fish length, and x3 = fish weight. Conduct a complete residual analysis of the model using the data in the FISHDDT file. Do you recommend any modifications to be made to the model? Explain.