1. The side length of this cube frame is 5cm. If all sides of a cube are covered with white paper, it should be at least (150) square centimeter or (1.5) square decimeter. The volume of this cube is (125) cubic centimeter, that is, (0. 125) cubic decimeter.

The cuboid has a volume of 72 cubic centimeters, a base area of 40 square centimeters and a height of (1.8 centimeters).

3. In a cuboid, the lengths of three sides intersecting a vertex are a cm, b cm and c cm respectively.

(1) Its surface area is (2ab+2ac+2bc) square centimeter;

(2) Its volume is (abc) cubic centimeters.

4. The side length of a cube is one centimeter, the surface area is (6 square) square centimeter, and the volume is (1 cubic) cubic centimeter.

5. The shape of the iron water pipe used for running water on the external wall of the building is cuboid. How many square decimeters of iron sheets are needed to make such a water-saving pipe (as shown in the figure, unit: decimeter)?

(1×15+0.6×15) × 2 = 48 (square decimeter)

A: At least 48 square decimeters of iron should be used.

6. The floor of the school practice room is rectangular, and a wooden floor with a length of 1600, a width of 1 decimeter and a thickness of 0.3 decimeter is laid on the floor of the practice room. What is the area of the practice room? How many cubic decimetres of wood do you need to process these wooden floors? How many cubic meters?

1600×5× 1=8000 (square decimeter)

8000×0.3=2400 (cubic decimeter) =2.4 (cubic meter)

A: The building area of the training room is 8000 square decimeters. Processing these wooden floors requires at least 2400 cubic decimeters of wood. 2.4 cubic meters. (26 pages)