Answer
$V=363.623$ m$^3$
Work Step by Step
The volume of a pyramid is:
$V=\frac{1}{3}Bh$
So,
$V=\frac{1}{3}100h$
To find h, substitute the slant height and half of the base's length into:
$a^2+b^2=c^2$
In this case, we are solving for the leg of the triangle given that the hypotenuse is 12, and the other leg is 5.
$a^2+5^2=12^2$
$a=10.90$
$V=\frac{1}{3}100(10.90)$
$V=363.623$ m$^3$