A spherical ball of lead has a diameter of 7.5 cm. what is the mass of the sphere if lead has a density of 11.34 g/cm3? (the volume of a sphere is (43) Ïr3 where r is the radius.)

The diameter of the sphere is 7.5 cm, therefore its volume is

V = [ (4π) / 3] * (7.5/2 cm) ³ = 220.8932 cm³

The density of the lead ball is 11.34 g/cm³, therefore its mass is

m = (220.8932 cm³) * (11.34 g/cm³) = 2.5049 x 10³ g = 2.5048 kg

Answer: 2.5 kg (nearest tenth)