The composition of a sample of Wustite is $Fe_{0..93}O_{1.00}$.What percentage of the iron is present in the form of $Fe(III)$?

Question

$\begin{array}{1 1}(a)\;15.05\%& (b)\;14.04\% \\(c)\;15.00\%&(d)\;14\%\end{array}$