When food enters from esophagus, one of the functions of the stomach is to produce and release enzymes. These enzymes help in the digestive mechanism. The pH here is two (2) that provides the optimum acidity environment for the maximum activity of pepsin, a protein-digesting enzyme.
The clavichord is a European stringed keyboard instrument known from the late Medieval, through the Renaissance, Baroque and Classical eras. Historically, it was mostly used as a practice instrument and as an aid to composition, not being loud enough for larger performances. The clavichord produces sound by striking brass or iron strings with small metal blades called tangents. Vibrations are transmitted through the bridge(s) to the soundboard.
Pxrd.sys is a Windows driver. A driver is a small software program that allows your computer to communicate with hardware or connected devices. This means that a driver has direct access to the internals of the operating system, hardware etc.