Why can Marco hear the music, even though he is not in the same room as the speaker?

Sound Travels

Explanation:

Sound waves can travel, and that makes it so that even though Marco is in a different room, he can hear the music. Depending how loud the music is and how thick the walls car, the sound can travel through the walls.

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.