What is the surface area of a sphere with a diameter of 10 inches? a. 40π in2 b. 100π in2 c. 20π in2 d. 50π in2

Short Answer B
Step One
Find the radius
Spherical properties are generally calculated with the radius. You are given a diameter. the radius = 1/2 the diameter.

radius = d/2
radius = 10/2
radius = 5

Step 2
Find the surface area. 
The surface area formula = 4*pi*r^2
p = 3.14
r = 5

The surface area = 4 * pi * 5^2
The surface area = 4 * pi * 25
The surface area = 100 * pi

Answer 100 pi <<<< answer.