While attempting to tune the note C at 277 Hz, a piano tuner hears 5.00 beats/s between a reference oscillator and the string. (a) What are the possible frequencies of the string? (Give the frequencies to the nearest integer.) lower possible frequency higher possible frequency Hz Hz (b) When she tightens the string slightly, she hears 6.00 beats/s. What is the frequency of the string now? (Give the frequency to the nearest integer.) Hz (c) By what percentage should the piano tuner now change the tension in the string to bring it into tune? (Give a positive answer for an increase in the tension, or a negative answer for a decrease in the tension.) %