9.33. Is it necessarily correct that a convex polyhedron, in which: a) all edges and all dihedral angles are equal; b) all edges and all polyhedral angles are equal, is correct?
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Official solution
9.33. No, not necessarily. Consider a convex polyhedron, the vertices of which are the midpoints of the edges of a cube. It can be verified that this polyhedron has equal edges, all dihedral angles are equal, and all polyhedral angles are equal,
Source: NuminaMath-1.5,
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