Answer: 300 cubic inches
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Explanation:
Consider only one triangular prism for now. The top prism has a front face that is a triangle. This is the base. The bases of a prism are always parallel. If you want, tip the prism so that the base is sitting on the ground.
The area of this base is 15 square inches since,
Area of triangle = base*height/2 = 5*6/2 = 30/2 = 15
Multiply the area of this base by the height of the prism, which is 10 inches, so we end up with
volume of prism = (area of base)*(height of prism)
volume of prism = (15 square inches)*(10 inches)
volume of prism = 150 cubic inches
This is the volume of one prism, but we have two identical 3D objects. So simply double this value to get 2*150 = 300 cubic inches.