the correct question is
What are the dimensions of a box that would hold 250 cubic centimeters of juice and have a minimum surface area
we know that
The dimensions of a box that have the minimum surface area for a given Volume is such that it is a cube.
[volume of a cube]=b³
V=250 cm³
so
250=b³----------> b=6.30 cm
the dimensions of a box are 6.30 cm x 6.30 cm x 6.30 cm
the answer is
6.30 cm * 6.30 cm * 6.30 cm.
This is a cube of side 6.30 cm