Answer:
54 cubic inches
Explanation:
Just as the area of a triangle is half the area of a rectangle with the same dimensions, the volume of a triangular prism is half the volume of a rectangular prism with the same dimensions:
V = 1/2(LWH)
V = (1/2)(9 in)(4 in)(3 in) = 54 in³
The volume of Phil's block of cheese is 54 in³.