With 27 edges of 1 cm long, you can make a big square. You can take a piece from it, respectively, and meet the following conditions: 1) the surface area remains unchanged; 2) the surface area remains unchanged How can I get it?

With 27 edges of 1 cm long, you can make a big square. You can take a piece from it, respectively, and meet the following conditions: 1) the surface area remains unchanged; 2) the surface area remains unchanged How can I get it?

1. Take it from the top
2. Take it from the edge, except the top
3. Take it from the surface, except the vertex and edge

At least () small squares can form a large square. If the edge length of a small square is 5cm, then the surface area of a large square is () square
Cm

It takes at least (8) small cubes to make a big cube,
If the edge length of a small square is 5 cm, the surface area of a large square is (10 × 10 × 6 = 600) square cm

How to reduce the surface area of a large square with 27 small squares

1. Remove the surface area of the small cube from the 8 vertices of the large cube
2. The surface area of a large cube will be increased if it is taken on the edge of the large cube or taken off the six sides of the small cube
3. Remove one row, two rows or all of them and the surface area is reduced