A classmate is trying to get help with their physics homework from you and asks you to look at the solution to one of their problems. The problem is to find the wavelength of the third harmonic of a 16.0 cm string with fixed ends. Your classmate reasons that "since the ends are fixed there has to be a node on each end, and thus each consecutive harmonic after the first will correspond with dividing the length of the string in half. The third harmonic would, therefore, have half a wavelength of (16.0 cm / 2) 2 = 4.0 cm, and thus the wavelength of the third harmonic is 8.0 cm." Is your classmate's reasoning correct? If so, explain why. If not, explain what mistake they made.