Describe the intersection of the plane and the solid.
Observe the intersection of the plane.
Step 1: Since the plane passes through the solid is parallel to the base and the base is a rectangle.
The cross section formed by the plane and the solid is a rectangle.
Step 2: Also, If we look at the figure, the cross section of the intersection is a rectangle.
Hence the cross section of the intersection of the plane and the solid is a rectangle.