The first picture, if there are two subgraphs, should be the edge of a cube. If there is a cube (excluding the fixed one), there should be 12 edges, so the smallest one is a 3*3*3 cube.

The second question, four rectangles are spelled into an 8cm square. In other words, four rectangles are horizontally placed in four rows, which is a rectangle with a length of 8cm and a width of 2cm. If it is flattened into a cuboid, its length and width are 8 and its height is 2, which means 72 cubic centimeters, its length and width are 2 and its height is 8, which means 32 cubic centimeters.