Question

The surface area of a sphere having a diameter of 8 inches is:

Answer 1

64 is the correct answer

Answer 2

Answer: $A = 201.06\ in^2$ or $A = 64\pi\ in^2$

Step-by-step explanation:

The surface area of a sphere is calculated by the following formula

$A = 4\pi r^2$

Where r is the radius of the sphere

In this case we know that the diameter d of the sphere is

$d=8\ inches$

So the radius r is:

$r=\frac{d}{2}\\\\r=\frac{8}{2}\\\\r=4\ inches$

So the surface area of the sphere is:

$A = 4\pi (4)^2$

$A = 64\pi$

$A = 201.06\ in^2$