You run an animal shelter facility and are asked to purchase food supply for the next month. You normally purchase two types of food, Purina and Natural Choice. Purina costs \( \$ 180 \) per bag. Each bag weighs 80 pounds and can feed as many as six animals per month. The Natural Choice bag costs \( \$ 110 \), weighs 60 pounds, and can feed four animals per month. There is a new type of food, Pedigree, which you must consider purchasing. Pedigree food costs \( \$ 110 \) per bag. Each bag of Pedigree weighs 180 pounds and can feed as many as 16 animals per month. You have been given a maximum budget of \( \$ 2,800 \) for this purchase, although you don't have to spend that much. The facility has room for no more than 2,000 pounds. You can only buy whole bags of each food. Create an adequate mode and solve it in Excel to maximize the number of animals to be fed during the month.

Prove that for three sets \( \mathrm{A}, \mathrm{B} \) and C . \( (A \cap B)^{\prime}=A^{\prime} \cup B^{\prime} \) \( (A \cup B)^{\prime}=A^{\prime} \cap B^{\prime} \) Define Cartesian nroduct of two sets.

1. Two of the Eigen values of the matrix \( A=\left[\begin{array}{lll}2 & 2 & 1 \\ 1 & 3 & 1 \\ 1 & 2 & 2\end{array}\right] \) are equal to 1 each. Then solve the Eigen values of \( A^{-1} \).

Describe classification of models by function.

Which of the following is not correct? (a) Duality does not play any role in the post - opti mal analysis of on LPP. (b) The optimum simplex table provides informa tion about the status and worth of the resources in addition to the optimum values of the decision variables. (c) In the optimum solution of a profit maximization LPp, the total (optimum) profit must be equal to the total wortiof the resources. (d) To write the dual problem, it is necessary that its primal LPP must have all its variables as greater than or equal to zero.

Exorcise 3.11 . Let \( \mathrm{A}=\left(\begin{array}{ccc}1 & 2 & 3 \\ 4 & 5 & 6 \\ 3 & 6 & -5\end{array}\right) \). Find the matrix obtained from \( A \) by applying the following elementary row operation. \( \begin{array}{lll}\text { a. } R_{1} \leftrightarrow R_{3} & \text { b. } R_{2} \rightarrow R_{2}-4 R_{1} & \text { c. } R_{3} \rightarrow \frac{1}{3} R_{3}\end{array} \)