Question

Find the surface area of a sphere with a diameter 18 cm. Round your answer to the nearest hundredth.

a.
768 sq. cm
c.
798 sq. cm
b.
1017 sq. cm
d.
1987 sq.cm


Please select the best answer from the choices provided

A
B
C
D

Answer 1

b.

1017 sq. cm

Explanation:

Surface area:

The surface area of a sphere with radius r is given by:

`S = 4\pi r^2`

In this question:

Diameter of 18, since the radius is half the diameter,
`r = (18)/(2) = 9`

The surface area is:

`S = 4\pi*9^2 = 1017`

So 1017 square centimeters, and the best option is b.