A right circular cone is 2.6 cm high, and the radius of its base is 1.5 cm. It is melted and recast into another right circular cone with a base radius of 1.3 cm. Find the height of the new cone.

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?