(a) A piano string of length 0.6 m is under a tension of 300 N and vibrates with a fundamental frequency of 660 Hz. What is the mass density of the string? (b) What are the frequencies of the first two harmonics? (c) A flute organ pipe (opened at both ends) also plays a note of 660 Hz. What is the length of the pipe? (you may take the speed of sound as V = 340 m/s).