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The human ear canal is approximately 2.5 cm long. It is (m)gr* rx :tle00: mipn :pkudopen to the j2lsyz o 0fdtti737*9 ztt5 vq.k,pyrh 1 a;oaoutside and is closed at the other end by the eardrum. Estimate the frequencies (in the audible range) of the standk 0yt17a5ta., j9r;p2 3zo*thzdtqis vy7f oling waves in the ear canal. What is the relationship of your answer to the information in the graph of Fig. 12–6? $f_1$ = Hz $f_3$ = Hz $f_5$ = Hz