4. This packaging method needs to bind the gift box twice, so the color ribbon required for packaging the gift box is = (10+20) × 2× 2 = 30× 4 =150cm, and the total length is120+50 =/kloc.

5. The volume of a large cuboid =5×2× 1.5= 150m? Because 150 cuboids have the same volume, the volume of each cuboid =150 ÷150 =1m? . 1m？ = 1000dm？ . (It can be written as follows: 1 m = 10 decimeter, 1 m3 =10x10 =1000 m3)

6. The fence area = (length× height+width× height) × 2 = (18× 3.3+12× 3.3) × 2 = 30× 3.3× 2 =198m2, and the roof area = length× width.