If the outer diameter of a spherical shell is 18 cm and the inner diameter is 12 cm, then find the volume of metal contained in the shell (take π = 3.14) correct to two places of decimal.

Find the approximate volume and surface area of a sphere of radius 6 cm. (Use π = 227)

Ram has two spherical balls of radius 10.5 cm each and Meena has six spherical balls of radius 7 cm each. What is the total volume of the balls that Meena has?