The volume is = Area of base x height (if that is a quadrilateral, but i think it is)
so get the area of the base which is = {(4x + 2)cm}²
and the volume of the container is = Area of base x height so
the final formula is {(4x + 2)cm}³
just solve
(4Xcm + 2cm)³
then multiply to itself three time you get this
=64Xcm³ + 8cm³
that's the volume :)  (but i'm not sure, i'm not that smart)
1 5 1
You cube (4x+2)
64x cube+ 96x squared+ 48x+ 8

I'm sure *^_^*