The base of a right pyramid is an equilateral triangle, each side of which is 20 cm. If each slant edge is 30 cm, then the vertical height (in cm) of the pyramid is:

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?