Question

A)
Calculate and compare the surface area of sphere A, which has a radius of 4in and sphere B whichhas a radius of 10 in. The formula for the surface area of a sphere is
(1 point) 4πr2
Sphere A has a surface area of and sphere B has a surface area of , meaning sphere B's
surface area is 5 times as large as sphere A's.
16π in2 40π in2
Sphere A has a surface area of and sphere B has a surface area of , meaning sphere B's
surface area is 2.5 times as large as sphere A's.
8π in2 20π in2
Sphere A has a surface area of and sphere B has a surface area of , meaning sphere
B's surface area is 6.25 times as large as sphere A's.
64π in2 400π in2
Sphere A has a surface area of and sphere B has a surface area of , meaning sphere B's
surface area is 4 times as large as sphere A's.
4π in2 10π in2

Answer 1

Surface area = 4πr^2.

Sphere A: 4π(4^2) = 4π(16) = 64π in^2.
Sphere B: 4π(10^2) = 4π(100) = 400π in^2.

Ratio B/A = 400π / 64π = 400/64 = 25/4 = 6.25.

So the correct choice is: 64π in^2 and 400π in^2, and sphere B's surface area is 6.25 times sphere A's.