Question

PLEASE HELP IM SO CONFUSED What is the surface area of a sphere with a radius of 9 units?

Answer 1

4 x pi x 9^2 
the answer is D

Answer 2

Answer:

The answer is D.$324\pi(units)^{2}$

Step-by-step explanation:

Given a sphere of radius R, the surface area of the sphere can be calculated using the following equation :

$A=4\pi(R)^{2}$

The area depends of the variable R ⇒

$A(R)=4\pi(R)^{2}$

To find the surface area, we replace $R=9units$ in the equation ⇒

$A(9units)=4\pi(9units)^{2}=4\pi81(units)^{2}=324\pi(units)^{2}$

The correct answer is D.$324\pi(units)^{2}$