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7. A Serum Iron analysis is done as follows, a) To 1.00 mL of serum sample is added 2.00 mL of reducing agent and 2.00 mL of acid to reduce and release Fe from transferrin. b) The serum protein, transferrin is precipitated with 1.00 mL of 30 % trichloroacetic acid and the mixture centrifuged to remove the protein (assume the volume of the remaining solution is unaffected by the mixing and is 1.00 +2.00+ 2.00+ 1.00 -6.00 mL) c) A4.00 mL aliquot of this solution is transferred into a test tube and treated with 1.00 mL of a solution having ferrozine and buffer. The absorbance is then measured to be 0.129. d) For an absorbance standard, 1.00 mL solution containing 3.00 ug of Fe is diluted to 6.00 mL with other reagents. Then 4.00 mL of this solution is treated with 1.00 mL of a solution having ferrozine and buffer and absorbance measured. To be 0.239. e) Blank solution has an absorbance of 0.038. g) All absorbance measurements are done using a 1.00 cm cuvette at 562 nm. Calculate the concentration of Fe in the serum sample