Formulate the following problem as a linear programming problems. Clearly state the objective function and the constraint equations for each problem. (Note: you don't need to find the final answer using excel solver) a) There are four different types of food diet: Diet 1, Diet 2, Diet 3, Diet 4 , with nutrition values and cost per unit as follows: Diet 3 Diet 4 150 500 4 1 5 $0.50 $ 0.20 $0.30 $ 0.80 Find a minimum-cost diet that contains at least 500 calories and at least 8 grams of fat. Calories Fat Cost Diet 1 400 2 Diet 2 200