Answer:
866.25 cubic centimeters (cm^3)
Explanation:
The formula for a triangular prism is the area of the base (the triangle part) multiplied by the height.
The area of a triangle = 1/2(base)(height)
The base of your triangle is 10cm, the height is 8.25.
a = (1/2)(10)(8.25)
a = 41.25 centimeters squared
Now we multiply that area (41.25) by the height of 21cm
21 x 41.25 = 866.25 and it's centimeters cubed (m^3) because it's volume, not area.
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