Some are some are not. Two regular pentagons with one equal side are congruent.
Yes providing that they are regular 5 sided pentagons otherwise no if they are irregular pentagons
A polyhedron with 12 congruent faces is a dodecahedron.
Yes
If they are congruent they must be similar.
A dodecahedron.
Yes. One can have congruent pentagons.
Yes.
Yes providing that they are regular 5 sided pentagons otherwise no if they are irregular pentagons
you don't
Yes
A polyhedron with 12 congruent faces is a dodecahedron.
An object with 2 congruent pentagons at opposite ends connected with 5 rectangles is a pentagonal prism.
If they are congruent they must be similar.
A dodecahedron.
A pentagonal prism.
Nothing
More or less two identical pentagons side by side.