The given figure is a rectangular prism.
The volume of a rectangular prism is given by
Where l is the length, w is the width, and h is the height of the rectangular prism.
The volume of the figure shown is 576 cubic in for the following dimensions.
Length = 8 in
Width = 6 in
Height = 12 in
If the height is changed to 6 in, then the volume is
Therefore, the volume of the figure will be reduced to 288 cubic inches if the height is changed to 6 inches.