A square pyramid is a 3 Dimensional image. When you slice a 3 Dimensional image you form is a 2 Dimensional image for example a rectangle, a square, a triangle e.t.c.
The shape of the cross sections formed after slicing a 3 Dimensional image is dependent on the way it was sliced.
This means it can be sliced horizontally or vertically and this would result in different shapes.
If square pyramid is sliced parallel to the base and halfway up the pyramid, the shape of the cross section formed is a square smaller than the base.
