The answer depends on the size of the polyhedron, whether or not it is convex and if so, whether or not it is regular.
Each surface of a polyhedron is called a face.
a base
It is called the surface area.
A face.
Add up the surface area of each of the polygonal faces. There may be a short cut available if it is a regular polyhedron so that all the polygons are the same.
It is a face of the polyhedron
Each surface of a polyhedron is called a face.
Because that is how a polyhedron is defined.
Because that is how a polyhedron is defined.
Its surface, would you believe!
a base
It is called the surface area.
that's a statement, but if you ment to say are the... then yes
Face
A face.
They are its faces
NO a cone is not a polyhedron as it has a curved surface. Similarly sphere and cylinders r 3D but not polyhedrons