Assertion: octahedron's ax | /r/HasProperty | threefold
Facets:
Source sentences:
text: the regular octahedron has three axes of fourfold rotational symmetry, four threefold axes and six twofold axes; the moment of inertia is presumably different for these three kinds of axis.
text: The only axes of rotational symmetry are three mutually perpendicular twofold axes and four threefold axes.