If the base radius and height of a cylinder are 4 cm and 5 cm, respectively, find the curved surface area of the cylinder. [use π = 3.14]

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?