An acceptable noise criterion rating for the background noise in a la…

Question

Prompt

An acceptable noise criterion rating for the background noise in a laundry room is

50

. For a noise criterion rating of

50

, the equation

y = 22 (0.997)^{x - 60} + 47

gives the estimated sound pressure level,

y

, in decibels, as a function of the octave band center frequency,

x

, in hertz, where

x \geq 60

. Which of the following is the best interpretation of

47

in this context?

47

22

less than the estimated sound pressure level, in decibels, at an octave band center frequency of

60

hertz.

47

22

less than the estimated sound pressure level, in decibels, at an octave band center frequency of

0

hertz.

47

is the estimated sound pressure level, in decibels, at an octave band center frequency of

60

hertz.

47

is the estimated sound pressure level, in decibels, at an octave band center frequency of

0

hertz.