Answer:
111.3 mm³
Explanation:
First, find the height of the pyramid by using the Pythagorean Theorem
Imagine a right triangle going through the middle of the pyramid and perpendicular to the base. The slant of the pyramid is the hypotenuse.
The formula for the height of the pyramid is h²=l²-(s/2)², the slant height takes the place of c, the leg of the right triangle takes the place of b, and the height of the triangle takes the place of a
square root both sides: h=√20²-(22/2)²
simplify exponents: h=√400-121
subtraction: h=√279
square root: h≈16.7
Then, solve for the volume like normal 1/3·b·h
20·16.7=334
334÷3≈111.3 mm³