The density and pressure variations in the graphic representation of a sound wave illustrate how these properties change with distance as the wave propagates through the medium, showcasing the compressions and rarefactions within the wave.

In the graphic representation of a sound wave, pressure variations are typically depicted by fluctuations of the curve above and below the average pressure value, similar to density variations.

Graph (c) represents how pressure changes as a sound wave moves through the medium, with fluctuations occurring above and below the average pressure value.

The density variation in a sound wave is represented by the fluctuations of the curve above and below the average value of density as the wave propagates in the medium.

One can expect to learn more about transverse waves in higher classes as part of advanced physics studies.