ANSWER
The multiplication, CA is defined, and its dimension is 3×2
EXPLANATION
Matrix A is a 2x3 matrix.
Matrix C is a 3×2 matrix.
The product of the two matrices , CA, is defined if and only if the inner product of their dimension are the same.

The inner products are the same.
Hence the matrix multiplication, CA is defined and its dimension is the outer products.

First covert the feet to meters.
1 meter = 3.3 feet.
Divide the total number of feet by 3.3 to get total number of meters:
198 / 3.3 = 60 meters per second.
Multiply meters per second by 15 seconds:
60 x 15 = 900 meters in 15 seconds.
For every meter there are 3.281 feet. The perimeter of the yard is 188ft. Divide 188 by 3.281 and you get 57.3 (rounded to 1dp). Round that<em> up</em> to the nearest meter and you get 58. So, Mr Smith needs 58 meters of fencing for his yard.
The mean, because the data distribution is skewed to the right