What kind of macromolecule is lactose? how do you know? (the 4 macromolecules are 1)carbs 2)lipids 3)amino acids and 4) nucleic acids)?

According the inverse square law, doubling the distance from the source of the sound, a speaker, for example, will drop the sound 6 db each time. if you were standing in the back of an auditorium, 32 feet away from a speaker not using any amplification, would you be able to hear a speaker clearly? why or why not?