6. Which expression represents the volume of the composite figure
formed by a hemisphere with radius r and a cube with side length 2r?

A. ( + 8)

Step-by-step explanation:

A composite figure is formed by two or more shapes in contact.

Volume of a cube =

where l is the length of its sides.

Given that l = 2r, then;

volume of the cube =

                                 = 8

volume of the cube = 8

For a hemisphere, volume =

Also,

volume of the hemisphere =

So that,

volume of the composite figure = volume of the cube + volume of the hemisphere

                                                 = 8 +

                                                 = (8 +  )

volume of the composite figure =  ( + 8)