1. Find the volume of the rectangular prism. In this case it would be 3 1/2 x 2 1/2 x 1 1/2 = 13 1/8.
2. Now you need to find how many cubes are needed to fill it. Basically since it takes 8 1/2 cm cubes to fill a 1 cm cube, you need to multiply 8 by 13 1/8. I got 105.
The answer is A.
