Concept explainers
Decibel levels. The decibel level of Professor Stout’s voice decreases with the distance from
the professor according to the formula
where
a. Find the decibel levels at distances of
b. How far must a listener be from the professor so that the decibel level drops to
c. Express L in the form
d. Express
as a function of
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Precalculus: A Unit Circle Approach
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