2.9*6*5=270 cubic centimeters, sawed into small cubes with a side length of 1 cm and a volume of 1 cubic centimeter, so there are 270 cubes. If the sum of the surface areas is 1* 1*6=6 cm2, then 6*270= 1620 cm2. No matter how many pieces are cut, draw eight corners of a cube on three sides, just like the Rubik's cube. 4. Imagine this problem as a Rubik's cube, and draw 36 faces, except for the eight corners, all of which draw three faces, and two faces are drawn in the middle of each side, so 12 sides have 12x = 5*5*5= 125 small cubes. 5.3 Continuous even numbers can be set to x, 2+x, 4+x, and the sum of side lengths is 72 decimeters, so x=4, so the length, width and height are 4, 6 and 8 respectively. The surface area is 4 * 6 * 4+4 * 8 * 4+6 * 8 * 4 = 416cm2. Landlord, I can't answer the first question. I'm sorry, I worked hard on these problems, but I finished them. I hope it works for you.