Regular Polyhedron     A solid, three-dimensional figure each face of which is a regular polygon with     equal sides and equal angles. Every face has the same number of vertices, and the     same number of faces meet at every vertex. An inscribed (inside) sphere touches     the center of every face, and a circumscribed sphere (outside) touches every vertex.     There are five and only five of these figures, also called the Platonic Solids:     the tetrahedron, cube, octahedron, dodecahedron, and icosahedron.
	Number of vertices: v Number of edges: e Number of faces: f Edge: a Radius of circumscribed sphere: R Radius of inscribed sphere: r Surface area: S Volume: V Dihedral angle between faces: delta (in degrees)
	To read about regular polyhedra, visit The Geometry Center: Regular Polyhedra Mathematics Encyclopedia: The Platonic Solids Eric Swab: Cube as the Base To explore polyhedra via an MJA applet, try Suzanne Alejandre's Studying Polyhedra For many more facts and links, see Alexander Bogomolny's Regular polyhedra For a Java applet showing many other polyhedra, see John N. Huffman's Crystallographic Polyhedra

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