What is the intensity level of a sound with an intensity of 0.000127 W/m2?

65 dB

72 dB

81 dB

120 dB

DB = 10 log (I/Io)

Where, Io is the reference intensity which is the minimum intensity that human can hear.

That is; Io = 10^-12

Therefore;

dB = 10 log (0.000127/10^-12) = 80.79

= 81 dB

Therefore; the correct answer is 81 dB