The diameter of a circle is 4.8cm, the circumference is () cm, the radius is () cm, and the area is () square centimeter

The diameter of a circle is 4.8cm, the circumference is () cm, the radius is () cm, and the area is () square centimeter

The perimeter is 4.8 × 3.14 = 15.072cm
The radius is 4.8 △ 2 = 2.4cm
The area is 2.4 × 3.14 = 18.0864cm;

The diameter of a circle is 8cm, its circumference is () cm, and its area is () square cm

The diameter of a circle is 8cm, its perimeter is (25.12) cm, and its area is (50.24) square cm

The diameter of a circle is 8cm, its radius is cm, its perimeter is cm, and its area is square centimeter
The second question is to cut out the largest circle from a piece of iron 12 cm long and 8 cm wide, and its remaining area is square centimeter

Radius 8 △ 2 = 4cm
Perimeter 3.14 × 8 = 25.12 cm
Area: 3.14 × 4 × 4 = 50.24 square centimeter
The radius of the circle is 8 / 2 = 4cm
The remaining 12 × 8-3.14 × 4 × 4 = 45.76 square centimeter

The radius of a circle is 4cm, its perimeter is () cm, and its area is () cm

The radius of a circle is 4cm, its perimeter is (25.12) cm, and its area is (50.24) cm ^ 2
Pay attention to the unit of area~