7. Because the ear is sensitive over a broad range of intensities, a logarithmic measure of intensity called sound intensity level is often used. The chosen reference intensity I₀ is approximately the threshold of human hearing at 1000 Hz. If the intensity of a sound wave equals 10 I₀, what is the sound intensity level in dB?
(A) -3
(B) 1
(C) 3
(D) 10
(E) 20

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