Answer:
Sketch of a cube with side = 4 in as shown.
The shaded area is perpendicular to the right and left vertical faces of the cube, so the cross section is a square with each side equal to 4 in.
The area of the cross section is
4*4 = 16 in²
The perimeter of the cross section is
4+4+4+4 = 16 in.
