Only the smaller cubes in the middle of each face of the original cube have exactly one face painted. There are 6 faces and each face has 1 middle cube, so 6 faces x 2 cubes per face = 12 cubes.
The given net is a standard net for a cube, where 6 squares form the 6 faces of a cube when folded.
A cube is least likely to resemble a pentagon when viewed from any angle, as it typically appears as a square, hexagon, or triangle based on perspective.
Rotating a rectangle around its vertical axis will form a cylinder.
The given net can be folded to form a pyramid with a square base or a tent-like structure but not a triangular prism, which has a different net structure.