Point groups in three dimensions the finite subgroups of SO(3), are: the cyclic groups "C" (the rotation group of a canonical pyramid), the dihedral groups "D" (the rotation group of a uniform prism, or canonical bipyramid), and the rotation groups "T", "O" and "I" of a regular tetrahedron, octahedron/cube and icosahedron/dodecahedron. In particular, the dihedral groups "D", "D" etc. are the rotation groups of plane regular polygons embedded in three-dimensional space, and such a figure may be considered as a degenerate regular prism. Therefore, it is also called a "dihedron" (Greek: solid with two faces), which explains the name "dihedral group". The rotation group of
A Plane Is Born of paint and Mark applies the decals to make it unique. Finally it is the turn of Tony Palmer to show us his own pride and joy - his Avid Speedwing. - Up, Up & Away! The final episode in the series sees the newly built plane go through the final checks it needs for its certificate of air-worthiness. Will it pass and can Mark finally realise his dream to fly his very own aeroplane? A Plane Is Born A Plane is Born, presented by Mark Evans, was a 15 part series for Discovery Home and Leisure (now Discovery Real