A sound wave is a pressure wave
that results from the vibration of the particles o the medium from the source.
The motion of the particles in the medium is parallel to the direction of the
energy transport. The type of wave formed by a sound wave is the longitudinal
wave. The answer is letter C. A longitudinal wave is characterized by
rarefactions. When motion is detected from the source, the particle next to it
vibrates from its rest position and a progressive change in phase vibration is
observed at each particle within that wave. The result is that the energy is
transported from one region to the other.
A wheelbarrow consists of a lever to be able to lift the material, and a wheel to be able to move it horizontally. So in a sense, a wheelbarrow is a complex machine consisting of two simple machines.
