A. Hope this helped im sorry if its wrong
The easy answer: If, say, B is the zero matrix, i.e.
then
You would first need to find a common denominator for 3/8 and 1/3 the common denominator would be 24 because 8 times three is 24 and 3 times 8 is 24. After you find your common denominator your fraction becomes 9/24 + 8/24. This gives you 17/24.
The unit measure that is appropriate would be Cubic meters