I know this is kinda late, but...
You can solve this easily as long as you remember how to find the volume of a cube. v=a^3, when a means length. The length is 1/2 cm, or .5 cm.
So, v+.5^3, which equals .125 cm. Each cube has a that volume. Now, multiply that by how many actual cubes there are, 96.
96 * .125 = 12