A company wished to model the number of minutes required to unload shipments of drums of chemicals at its warehouse as a function of the number of drums and the total shipment weight in hundreds of pounds. The data from 20 consecutive shipments, from (Neter et al., 1996), are in the file (datasets/shipment .dat). 2.
a. Regress minutes on drums and weight, storing the residuals.
h. Interpret the regression coefficients of drum and weight.
c. Provide and discuss plots of the residuals against the fitted values and both predictors, and a normality plot.
d. Provide a 90% prediction interval for the time it would take to unload a new shipment of 10 drums weighing 1000 pounds