The answer to this problem would be B. Here are the steps:
So, the dimensions of the prism are: 9,3, and 7.
Multiply them all: 9×3×7=189
Lastly: you multiply 189×1/3=63 yd^3
Incase you are wondering, since each cube is 1/3 in length you multiply that by the volume of the prism.
Hope this helps (:
