Prism
There can be no such shape. If there were a shape with n flat surfaces, then if you sliced off one vertex, you would have a shape with n+1 flat surfaces. So it is always possible to add one more flat surface.
One whose boundaries are straight lines.
true
A sphere
Flat shapes such as polygons are two-dimensional.
a rectangle
true
A cube
a cylinder
cube There are a great many solid shapes that have only flat surfaces.
It is a cube or a cuboid