Two compact sources of sound oscillate in phase with a frequency of 120 Hz where the speed of sound is 340 m/s. At a point that is 4.3 m from one source and 4.7 m from the other, the amplitude of the sound from each source separately is A. What is the phase difference 6 in the sound waves from the two sources at that point? 8 = What is the amplitude A' of the resultant wave at that point, in terms of A? rad A' =