So far, we have analyzed a tube or rectangular cavity and determined the resonant frequencies of the cavity. Really, what is useful is the reverse. If we measure the frequencies we can determine the dimension(s) of the cavity. This will be true even if we cannot see the cavity directly (either it is too small or too far away). What length (in meters) of a closed-closed tube will produce the following set of frequencies: 208 Hz, 416 Hz, 624 Hz ? Assume the speed of sound is 343 m/sec