Which of the following are the measurable characteristics of sound?

The measurable characteristics of sound include frequency, intensity, and duration.

Frequency pertains to the number of sound waves that pass a given point in one second, typically measured in Hertz (Hz). It determines the pitch of the sound; higher frequencies result in higher pitches, while lower frequencies produce lower pitches.

Intensity, often measured in decibels (dB), refers to the power level of the sound. It is related to the amplitude of the sound waves; greater intensity corresponds to louder sounds.

Duration indicates how long a sound persists. It is an important characteristic because it can affect the perception of sound in various contexts, such as music or speech.

These three characteristics are fundamental to understanding sound in both physics and acoustics, making them the correct choice in this context. The other options include elements that might describe qualities of sound (such as volume) but are not measured characteristics in the same fundamental way as frequency, intensity, and duration.