the names of them are semiregular polyhedron
The sides of a rectangle are not all equal so a rectangle is not a regular polygon. And, as a consequence, any 3-dimensional shape made from rectangles cannot be a regular polyhedron.
No.
No, it is not.
An icosahedron is a regular polyhedron with 20 equilateral triangle faces.
It is not a regular polyhedron because it has unequal sides
a regular octahedron
the names of them are semiregular polyhedron
No. It is a semi-regular polyhedron. Explanation. The truncated icosahedron is a polyhedron that can be constructed from an icosahedron with the 12 vertices truncated (cut off) such that one third of each edge is cut off at each of both ends. This creates 12 new pentagon faces, and leaves the original 20 triangle faces as regular hexagons A regular polyhedron is a polyhedron whose faces are congruent regular polygons. The truncated icosahedron is NOT a regular polyhedron, it is a semiregular polyhedron. It is a uniform polyhedron.
No, a sphere is not a polyhedron.A polyhedron is a three-dimensional geometric figure whose sides are polygons.A regular polyhedron is a polyhedron whose faces are all congruent regular polygons.
The sides of a rectangle are not all equal so a rectangle is not a regular polygon. And, as a consequence, any 3-dimensional shape made from rectangles cannot be a regular polyhedron.
No.
No, it is not.
No. A polyhedron is 3 dimensional. You have a regular polygon, regular because the sides are equal. If you asked about 20 surfaces, then it would be a polyhedron.
No it isn't a regular polyhedron
An icosahedron is a regular polyhedron with 20 equilateral triangle faces.
Not necessarily. If all faces are equilateral triangles (all edges are equal length) then it is a regular polyhedron.