Intensity of Sound: A certain glass window reduces the intensity level of the sound from 72 dB to 47 dB. By what factor is the acoustic power reduced by this glass window?
A. 3.2 × 10-3
B. 2.2 × 10-2
C. 5.6 × 10-2
D. 1.0 × 10-1
E. 1.5 × 10-1
Answer: A
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