Does the schema plugin work?

Yeah, if this code is being displayed within the source code, then the schema plugin works.

How does sound travel?

Sound travels as waves of vibrating energy through a medium, such as air, water, or solids. When an object vibrates, it causes the surrounding medium to also vibrate, creating a chain reaction of vibrations that propagate through the medium. The sound waves consist of compressions and rarefactions, where the compressions are regions of high pressure and the rarefactions are regions of low pressure. These pressure changes in the medium are what our ears detect as sound. The speed of sound depends on the medium through which it travels, as well as the temperature and humidity of that medium. In general, sound travels faster in denser mediums, such as solids, than in less dense ones, such as gases. When sound waves encounter an obstacle, they can be reflected, refracted, absorbed, or diffracted depending on the properties of the obstacle and the angle of incidence of the waves. This is why sound can be heard around corners or through walls, and why some materials are better at blocking sound than others.