(Solved): Two identical sound sources produce identical sound waves with a frequency of 540Hz that are trav ...

Two identical sound sources produce identical sound waves with a frequency of $$540\mathrm{Hz}$$ that are travelling in the same direction at $$330\mathrm{m}/\mathrm{s}$$. If both sound waves have the same phase when they are emitted from the sources, what is the phase difference between the waves at a point that is $$4.40\mathrm{m}$$ from one source and $$4.00\mathrm{m}$$ from the other source at the same moment in time?