Hello!
The volume formula for a rectangular prism is length x width x height, so all we need to do is plug in the numbers.
L x W x H = V
12.5 x 4.5 x 4.2 = V
236.25 = V
Don't forget the units! We say cubed because the prism is 3-Dimensional but if it was 2-D we would say squared.
The volume is 236.25 centimeters cubed.