The prism is h=108 inches high, l= 20 feet long, and w= 8 feet width. Recall that 1 foot is 12 inches. This tells us that the height is h= 10812= 9 feet.
We are asked to find the volume of the truck, \textcolor{darkorange}{V_\text{truck}}. The volume of a right rectangular prism is equal to the product of its dimensions.