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Approximately a third of people with normal hearing have ears that continuously emit a low-intensity sound outward through the car canal. A person with such spontaneous otoacoustic emission is rarely aware of the sound, except perhaps in a noise-free environment, but occasionally the emission is loud enough to be heard by someone else nearby. In one observation, the sound wave had a frequency of 1665 Hz and a pressure amplitude of 1.13 × 10−3 Pa. What were (a) the displacement amplitude and (b) the intensity of the wave emitted by the ear?
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