What is the size of the matrix resulting from

B. 1×3

Step-by-step explanation:

Given the first matrix as [ 4  -1  0]  this is 1×3  (row by column)

The second matrix is [2  1   0  ] which is  a 3×3  matrix

                                   [-3  -7 2 ]

                                   [1  -5    2]

Hence the answer matrix will be;

[1×3 ] *[3×3]cancel the shaded numbers to remain with

[1×3]

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