9. To decrease the intensity of the sound you are hearing from your speaker system by a factor of 36, you can
(A) reduce the amplitude by a factor of 12 and increase your distance from the speaker by a factor of 3.
(B) reduce the amplitude by a factor of 4 and increase your distance from the speaker by a factor of 3.
(C) reduce the amplitude by a factor of 2 and increase your distance from the speaker by a factor of 3.
(D) reduce the amplitude by a factor of 3 and increase your distance from the speaker by a factor of 4.
(E) reduce the amplitude by a factor of 3 and increase your distance from the speaker by a factor of 12.

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