The answer depends on the number. Note that the question does not require the solids to be in the form of cubiods (rectangular prisms).
rectangular prisms (including cubes). maybe some other ones I'm not thinking of now too.
A rectangular prism that is 4 cubes by 2 cubes is made up of 8 cubes.
Cubes have a square on each side, but rectangular prisms have rectangles or squares.
There is no limit to the number of cubes which can be arranged on top of a rectangular prism.
A sphere. All other solids, including cubes, rectangular prisms, and cones all have at least one vertex.
No it is not
Cubes are special cases of rectangular prisms.
cubes
Depends on the dimensions of the prism, and how large of cubes they are.
A rectangular prism has two bases, each of which is a rectangle, and four rectangular sides. The 12 cubes are the same as the rectangular prisms, except that each of the rectangles is a square.
2