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Mathematics>Standard Multiple Choice

Read the following SAT test question and then click on a button to select your answer.

S=4πr^2

The formula above gives the surface area, S, for a sphere with radius r. Sphere A has a surface area that is 64 times greater than the surface area of sphere B. What is the ratio of the radius of sphere A to the radius of sphere B?

A.4:1
B.8:1
C.16:1
D.64:1

答案和解析

答案：D

解析：

Choice B is correct.