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The human ear canal is approximately 2.5 cmo890hh f2 fd- rwf rptrou6n(1 long. 4o;coa ite8v5uoz4e1 iryy h52gh+ d1It is open to the outside and is closed at thecrdo u514e58zihg1v;oay eyt2 o+h4i other end by the eardrum. Estimate the frequencies (in the audible range) of the standing 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