Given below are the oxides:\( \mathrm{Na}_{2}\mathrm{O}, \ \mathrm{As}_{2}\mathrm{O}_{3}, \ \mathrm{N}_{2}\mathrm{O}, \ \mathrm{NO} \) and \( \mathrm{Cl}_{2}\mathrm{O}_{7} \)Number of amphoteric oxides is:
\( 0 \)
\( 1 \)
\( 2 \)
\( 3 \)