Ross is building a model of a square pyramid for a class project. The side length of the square base is 18 inches and the slant height of the pyramid is 19 inches. What is the surface area of the model pyramid?

A. 666 in. 2

B. 684 in. 2

C. 1008 in. 2

D. 495 in. 2

Surface area of a square pyramid

= area of the base + 4 times area of one of the slanted faces

Area of the base = side length * side length = 18*18 = 324

Area of one slanted face = (1/2) * side length * slant height = 1/2*18*19 = 171

Surface area = 324 + 4 * 171

= 1008 in. 2

ans is C