A construction explosion has an intensity I of 1.25 x 10-4 W/m2. Find the loudness of the sound in decibels if W/m2. Round to the nearest tenth.

A. 81 decibels

B. 161 decibels

C. 82.2 decibels

D. 12.5 decibels

We solve this problem by using the decibels formula which is expressed as:

dB = 10 x log (Isig/Iref)

where dB is decibels, Isig is the intensity of the signal and Iref is the intentsity of the softest sound the human ear can hear which has a value of 10^-12.

We solve as follows:

dB = 10 x log (1.25 x 10-4 / 10^-12) = 80.97 decibels

Therefore, the correct answer is option A, 81 decibels.