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The amino acid tyrosine has an absorption peak at 290 nm. After appropriate treatment of a 0.2162-g sample to isolate the tyrosine, the sample volume was 250.0 mL. This solution had an absorbance of 0.118 in a 2.00-cm cell. A sample of pure tyrosine (MW = 181), weighing 126.4 mg, was dissolved in 100.0 mL of solution. A 10.00-mL aliquot of this solution, diluted to 250.0 mL, had an absorbance of 0.473 at 290 nm in a 1.00-cm cell. Calculate the percentage of tyrosine in the sample.