Answer:
V = 64 in.²
Explanation:
If the sides are 3 inches long, each, and we know that this is a box, this must be a cube. Being told to increase the side-lengths by 1 inch on every axis, we know have the side-length s = 4 in.
The volume of a cube can be determined by the equation:

(Simplify)
V = 64 in.²