Answer:
Option C. 6872.8 yd³
Explanation:
Since volume of the triangular prism = Area of square base × height of prism
Area of square base = length × width = 16×31 = 496 yd²
Height of the prism (By Pythagoras theorem) = Height of the isosceles triangle =

=

=
yd
Now we put these values in the formula of volume
Volume = 496×8√3 = 496×(13.86) = 6872.8 yd³
Answer is option C. 6872.8 yd³