Two Mirror Image Cube Construction Puzzles

Here are two simple puzzles each composed of 3 pieces which can be assembled into a cube. The cube is composed of sub cubes, 27 of which make a 3x3x3 cube. Piece 8a contains eight sub cubes, 9a nine sub cubes, and 10a ten sub cubes. The set of b pieces in the second puzzle are mirror images of the a pieces. The puzzles are not difficult but false starts can occur. To increase the difficulty one can add a piece or two with the opposite hand to a puzzle and tell the solver that only three pieces are needed to make a cube. To make it still harder the six pieces can be mixed together and the solver told that two cubes are required. OpenSCAD code is included.