Which of the following quantities is directly proportional to the gravitational pull between two objects?
Sum of their volumes
Product of their masses
Distance that separates them
Distance from their center to their surface

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?