The Howler Monkey Is the Loudest Land Animal And, Under

Multiple Choice

The howler monkey is the loudest land animal and, under some circumstances, can be heard up to a distance of 8.9 km. Assume the acoustic output of a howler to be uniform in all directions and that the threshold of hearing is 1.0 × 10^-12 W/m². A juvenile howler monkey has an acoustic output of 63 µW. What is the ratio of the acoustic intensity produced by the juvenile howler to the reference intensity I₀, at a distance of 210 m?

A) 110
B) 230
C) 76
D) 170
E) 300