Answer:
81 1-inch cubes
Explanation:
Cube root of 729 is 9
9 x 9 = 81
Further explanation:
A cube has 3 measures (there are all the same) to solve for the volume. If the volume is 729, and it is a cube, you would solve for the cube root, because all the numbers are the same. Then, we would get 9. Now, since a cube is made up of faces, and each one is a square, we do 9 x 9 to get the area, which is the answer, because 1-inch cubes are literally just units.