Rohan had a cuboidal box with dimensions 36 cm × 25 cm × 20 cm. He packed as many solid cubes as possible into it, each of which has edges of length 4 cm. How much empty space (volume) will still be left in the box?

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?