$3\mathrm{.}4-15.$ Joyce and Marvin run a day care for preschoolers. They$($d$)$ Use the spreadsheet to check the following solutions:

$(x_1,x_2)=(7,7),(7,8),(8,7),(8,8),(8,9),(9,8).$ Which of

these solutions are feasible? Which of these feasible solutions

has the best value of the objective function?

c $($e$)$ Use Solver to solve this model by the simplex method.

are trying to decide what to feed the children for lunches. They

would like to keep their costs down, but also need to meet the

nutritional requirements of the children. They have already de$-$

cided to go with peanut butter and jelly sandwiches, and some

combination of graham crackers, milk, and orange juice. The