Answer: Bethany is not correct
Explanation:
The volume of the box is the product of its three dimensions, length, width, and height. The product of a number of "inches" and a "pure number" (3 has no units given) will not be "cubic inches."
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As it happens, the cube-shaped box with a volume of 27 cubic inches will have a height of 3 inches and a side area of 9 square inches. The edge length of the cube is 3 inches, not 9.