Two speakers are positioned in such a way that, while each os producing sound, and observer nearby cannot hear any sounds. this shows that the speakers are creating a. constructive interference b. destructive interference c. vibrations d. oscillations

B. destructive interference

Explanation:

since the observer can't hear the sound then both speakers make sounds of the same magnitude and opposite in direction

the five characteristics of adolescence are biological growth and development, and undefined status, increased decision making, increased pressure and the search of self.

conservation of mass

mass before something happens = mass afterwards