I can't figure this out! I kept thinking I was doing it wrong but I'm not so sure.... What do you think it is? Please help!

Suppose each edge of a cube is 7.8 cm long. Which is the BEST estimate for the volume of the cube?

They must have given you a list of choices.

One estimate could be 8*8*8 = 64*8 = 480+32 = 512