8.1-5. Reconsider the P & T Co. problem presented in Sec. 8.1.You now learn that one or more of the shipping costs per truckload given in Table 8.2 may change slightly before shipments begin. Use the Excel Solver to generate the Sensitivity Report for this problem. Use this report to determine the allowable range to stay optimal for each of the unit costs. What do these allowable ranges tell P & T management?