1) Area; because covering the sauce over the "area" of the pizza.
2) We know we are covering a CIRCULAR pizza with a 16-inch diameter.
3) We need to find the AREA of the circle.
4)
Area of a circle is pi*r^2. r is the radius which is half the diameter.
So r = 8, r^2 = 64, and pi = 3.14
So area = 64*3.14 = 200.96 inches squared
Samantha will cover 200.96 square inches of the the pizza with sauce.