Explanation: formal writing system used in ancient Egypt. Hieroglyphs combined logographic, syllabic and alphabetic elements, with a total of some 1,000 distinct characters. Cursive hieroglyphs were used for religious literature on papyrus and wood.
The subject would be the noise in the building. Even though it occurs mid-sentence, it is what the whole sentence is about. The portion of information in front of the comma was just additional information.
