Problem: A large bat lets out a short burst of ultrasonic sound, which the smaller bat hears a moment later. If the large bat flies at 12.60 m/s and the small bat flies at 4.520 m/s, both towards each other. Assume that the speed of sound is 343.0 m/s. Some of the large bat\'s signal reflects off of the small bat and returns to the large bat, warning it of the smaller bat\'s presence. If the initial signal has a frequency of 77.30 kHz,
Part A: What return frequencies will the large bat detect?
Part B: Calculate the final frequency to four significant figures.
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