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1, area =1.5×1.5× 3.14+3× 3.14× 2.5 = 30.615m2.

2. The area to be drawn for each column (note that columns are not included) is 0.6×3. 14×5=9.42 (square meters).

Multiply by four, and then multiply by the processing fee of 0.6× 3.14× 5× 4× 5 =1884 (yuan) per square meter.

3. There are two situations.

Take 18.84 as the height of the cylinder and 12.56 as the circumference of the bottom.

Radius =12.56 ÷ 3.14 ÷ 2 = 2cm.

Bottom area =3. 14×2? = 12.56 (cm2)

Take 12.56 as the height of the cylinder and 18.84 as the circumference of the bottom.

4. Side area of cylinder = perimeter of bottom * length of bus of cylinder =3. 14* 1.5.

The area of rolling for 20 cycles =20* the side area of the cylinder = 20 * 3.14 *1.5 = 94.2 (square meter).

5. The perimeter of the bottom surface is 94.2÷ 3 = 31.4cm..

The bottom radius is: 3 1.4 ÷ 3. 14 ÷ 2 = 5cm.

Volume: 3. 14×5? × 10=7850 cubic centimeters

6. Bottom area: 3. 14*5*5=78.5 cm2.

Side area: 3.14 *10 *10 = 314cm2.

The area of the iron sheet is 78.5+3 14=392.5 square centimeters.

7. Height 12 decimeter =1.2m; Bottom diameter =1.2× 75% = 0.9m; Radius =0.45 meters.

Area of base circle =3. 14×0.45*2.

The side area of the cylinder =2×3. 14×0.45× 1.2.

Total area =100× (3.14× 0.45 * 2+2× 3.14× 0.45×1.2) = 402.705 square meters.

8, the bottom circumference is

6.281= 6.28 meters

The bottom radius is

6.28 ÷ 3. 14 ÷ 2 = 1m

It can be built on a rectangular open space 3 meters long and 2 meters wide.

Must be adopted, awesome! parents