if the radius of a sphere is tripled, the surface area of a sphere will increasea) by a factor of 3b) by a factor of 4c)by a factor of 6d)by a factor of 9

Respuesta :

Answer:

D

Step-by-step explanation:

The area and the radius of a sphere are related by the formula:

A=4πr^2

Let’s say this is A1 and r1

Now the radius is tripled. This means r2 = 3r1

The new area thus becomes: A = 4 * (3r)^2 * π = 36πr^2

Comparing A1 and A2 , we can see that A2 = 9A1