Given that Circumference of a great circle(C) = centimeters.

Circumference:

                (Substitute )

                         (Cancel common terms)

                    (Divide each side by 2)

Area of the great circle:

                               (Substitute )

                                 (Evaluate powers)

A hemisphere is half of a sphere. To find the surface area, find half of the

surface area of the sphere and add the area of the great circle.

Surface area:

                (Surface area of a hemisphere)

         (Substitute )

                       (Simplify)

                                  (Add: )

                         (Substitute )

                               (Multipl: )

The surface area is approximately 150.7 square centimeters.