Can anyone me what to derive formula until we finally obtained the formula of interference of sound wave which is , lambda = ax/d, a= distance between two speakers, x= distance between two consecutive loud sound, d = distance between the straight line path amd the two speakers

Argon, neon, and xenon are examples of

Assume that two of the electrons at the negative terminal have attached themselves to a nearby neutral atom. there is now a negative ion with a charge -2e at this terminal. what are the electric potential and electric potential energy of the negative ion relative to the electron? the electric potential and the electric potential energy are both twice as much. the electric potential is twice as much and the electric potential energy is the same. the electric potential is the same and the electric potential energy is twice as much. the electric potential and the electric potential energy are both the same. the electric potential is the same and the electric potential energy is increased by the mass ratio of the oxygen ion to the electron. the electric potential is twice as much and the electric potential energy is increased by the mass ratio of the oxygen ion to the electron.

What practical value did astronomy offer to ancient civilizations?