The diameter of a sphere is 4 centimeters. Which represents the volume of the sphere?

33.49cm³

Step-by-step explanation:

Volume of sphere =4/3πr³

diameter = 4cm

radius = diameter/2 = 4/2 = 2

Volume of sphere =4/3πr³= 4/3 x 3.14 x 2³ = 4/3 x 3.14 x 8 = 4/3 x 25.12 = 4x25.12/3 = 100.48/3 = 33.49cm³

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.