An unknown Cu solution was prepared by dissolving $3\mathrm{.}2126g$ of the sample in a $200\mathrm{.}0mL$ flask. A $25\mathrm{.}00mL$ aliquot of this solution was titrated with $0\mathrm{.}1041MN{a}_2{S}_2{O}_4,$ the titration required $17\mathrm{.}59mL$ to reach the end point. Calculate the $\%$ Cu in the sample. Give your answer to $2$ places after the decimal point. Do not enter units.