SalesLet matrix A represent the sales (in thousands of dollars) for the Walbash Company in 2011 in…

Sales

Let matrix A represent the sales (in thousands of dollars) for the Walbash Company in 2011 in various cities, and let matrix B represent the sales (in thousands of dollars) for the same company in 2012 in the same cities.

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<p>(a) Write the matrix that represents the total sales by type and city for both years.</p>
<p>(b) Write the matrix that represents the change in sales by type and city from 2011 to 2012.</p>
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