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The human ear canal is approximately 2+u, t-40b(z qkh0asa5,h qa-owl rech.5 cm long. It is opno2dv; (ltpbhwu(*: sen to the outside and is closed at the other end by the eardrum. Estimate the frequencies (in the audible range) of the stanv(dh ;: wlos2p u(tn*bding 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