There is small pond which is 8 metres long, 4metre wide and 2metre deep what is the volume

The expression 6x2 gives the surface area of a cube, and the expression x3 gives the volume of a cube, where x is the length of one side of the cube. find the surface area and the volume of a cube with a side length of 6m

Ineed i been stuck on this question since yesterday

Which number completes the inequality? 2/3 < _ < 7/9