Find the volume of the sphere and the area of the sphere if: 1) the radius is 5 cm 2) the diameter is 0.3 dm

1). Ball volume: V = 1 1/3 P R³;

Sphere area: S = 4 P R²;

V = 1 1/3 * 3.14 * 5³ = 4/3 * 3.14 * 125 = 4/3 * 314/100 * 125 = 4/3 * 314/4 * 5 =

= 1/3 * 314 * 5 = 1570/3 ≈ 523.33 (cm³);

S = 4 * 3.14 * 5² = 4 * 25 * 3.14 ≈ 314 (cm²);

2). V = P D³ / 6; V = 3.14 * (0.3) ³ / 6 = 3.14 * 27/10: 6 = 3.14 * 9/20 ≈ 1.413 (dm³);

S = P D² = 3.14 * (0.3) ² = 3.14 * 0.09 ≈ 0.28 (dm²).