The Howler Monkey Is the Loudest Land Animal And, Under

question 30

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

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Definitions:

Ammonia

A compound of nitrogen and hydrogen with the formula NH3, characterized by its pungent smell and used as a fertilizer and cleaning agent.

2-Phenylethylamine

An organic compound with the formula C8H11N, characterized by a phenyl group attached to an ethylamine.

Toluene

A mono-substituted benzene derivative, where a methyl group replaces one hydrogen atom, used widely as an industrial solvent.

Synthesis

The process of combining different entities to form a new, complex product, often used in the context of chemical synthesis.