The formula for determining the volume of a triangular prism is expressed as
Volume = area of triangular face * height of prism
The fotmula for finding the area of the triangular face is
Area = 1/2 * base * height
Looking at the diagram,
base = 8 cm
height = 10 cm
Area of triangular face = 1/2 * 8 * 10 = 40 cm^2
height of prism = 20 cm
Volume of prism = 40 * 20 = 800 cm^3
Option B is correct