Answer:


Explanation:
Given
See attachment for complete question
Solving (a): The entry C22
First, matrix C represents the inventory at the end of July.
The entry of C is calculated as:

i.e.
![C = \left[\begin{array}{ccc}543&356&643\\364&476&419\\376&903&409\end{array}\right] - \left[\begin{array}{ccc}102&78&97\\98&87&59\\54&89&79\end{array}\right]](https://img.qammunity.org/2022/formulas/mathematics/college/m559v2hynkbrz6bes3j942j52bimqkrywe.png)
![C = \left[\begin{array}{ccc}543-102&356-78&643-97\\364-98&476-87&419-59\\376-54&903-89&409-79\end{array}\right]](https://img.qammunity.org/2022/formulas/mathematics/college/70gdq4t3qvm69rpqyi0nu3syqlj8lvvcd3.png)
![C = \left[\begin{array}{ccc}441&278&546\\266&389&360\\322&814&330\end{array}\right]](https://img.qammunity.org/2022/formulas/mathematics/college/8r6lvcjnqj98nc4w0aib3dsqexc9kfso21.png)
Item C22 means the entry at the second row and the second column.
From the matrix

Solving (b): The maximum A31 possible.
From the given data, we have:
![Inventory = \left[\begin{array}{ccc}543&356&643\\364&476&419\\376&903&409\end{array}\right]](https://img.qammunity.org/2022/formulas/mathematics/college/16vxt0p9dufv9nucuayxhm874a3l2g4qlk.png)
![Unit\ Sales = \left[\begin{array}{ccc}102&78&97\\98&87&59\\54&89&79\end{array}\right]](https://img.qammunity.org/2022/formulas/mathematics/college/l9laf21o92t3kycjq2sxtzufg9nfu9uk6u.png)
From the matrices above.
A31 means entry at the 3rd row and 1st column.
So, the possible values of A31 are:

and

By comparison, 376 > 54
So: