A hiker has various cans of food of assorted sizes that are to be placed in a knapsack. Unfortunately, the knapsack is not large enough to hold all the cans. Therefore, the hiker must determine which cans are to be included in the knapsack. suppose that a hiker's knapsack will hold no more than 0.8 cubic feet of canned goods. The hiker would like to make a selection that will maximize the total protein content of the food in the knapsack. Some food items that are being considered for inclusion in the knapsack are shown in Table 7.1. TABLE 7.1 Items That Might Be Selected for Inclusion in a Knapsack Item 1 2 3 4 5 Volume. cubic feet 0.2 0.5 0.2 0.2 0.3 Grams of protein 12 40 0 15 20 10 a. How should the hiker pack his bag? b. What happens to the solution if the hiker wants to include item 2 and 3 for sure? c. What happens to the solution if the hike decides to include at least one of can 2 and 3?