Answer: 96 cubic feet (choice D)
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Explanation:
The triangular face has area of base*height/2 = 8*2/2 = 16/2 = 8 square feet.
Multiply this with the depth of the prism to get 8*12 = 96 cubic feet
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For any prism, the volume formula is
V = (area of base)*(depth of prism)
The term "depth" can be replaced with "height" and it's the same idea.
In this problem, we have a triangular prism because the parallel sides are triangles.
