1.1 Parcel Company in charge with transporting goods to customers wants to determine which items to assign in 2 bags in order to maximize the total values. There are 6 single items with differences in term of weight, volume, and value (shown in table 1) waiting to put into 2 bags (Knapsacks). The first bag has 100 kilograms as its weight capacity and 3000 cm as a volume capacity. The second bag has 200 kilograms as its weight capacity and 4000 cm as a volume capacity. It can be noted that each item has only one piece so that this problem is considered 0-1 knapsack problem. Formulate the mathematical model for this problem. (15 point) Table 1: Characteristics of items Items 1 Weight (Kg) Volume (cm) Value 20 100 75 2 70 50 65 3 80 70 95 4 30 45 55 5 90 80 85 6 45 120 105