Good Explanation needed!

Question

first i know its a cube what i did to solve this question is did...

4.5x4.5x4.5 = 91.125 correct if not please explain what i did wrong

Answer 1

you did it right.

actually even without really doing the full calculation, you can tell d) is the only possibly correct answer.

4.5 is more than 4. 4^3 = 4x4x4 = 16x4 =64. So you know the volume is some number greater than 64. If this were a time pressure test, you could choose d) and be confident it's the best answer. a), b) and c) are too small.