Which of the following two oxide of nitrogen have 30.5% nitrogen

Question

$\begin{array}{1 1}(a)\; NO_4 \;and\;O_2 \\ (b)\;NO_2\;and\; N_2O_4\\(c)\;N_2O_2 \;and\; O_2\\(d)\;N_2O_5\;and\;CO_2\end{array}$