In (16), the term (m-1)GPM1 represents the amount of fuel gallons used by m-1 full trucks. The rest of the term represents the gallons of fuel used by the last truck which depends on the capacity utilized. The linear relation between the fuel consumption by the last truck and the capacity utilized is illustrated in Fig. 4. Adding those terms together yields the amount of fuel consumed by all trucks, which is then multiplied by the emission level per gallon of fuel (CEGF) to obtain the carbon emissions produced by the upstream transportation activity. In a similar fashion, the carbon emissions due to transporting the cold item from the DC to the retailer is given by: