What is the magnetic nature of dioxygen $(O_2)$?

Which of the following species is paramagnetic?

How many molecular orbitals filled with one or more electrons are present in $N_2^+$?

Among the following groupings,which represents the collection of isoelectronic species?

Given below are two statements:
Statement $(I)$: The correct sequence of bond lengths in the following species is:
$O_2^+ < O_2 < O_2^- < O_2^{2-}$
Statement $(II)$: The correct sequence of number of unpaired electrons in the following species is:
$O_2 > O_2^+ > O_2^- > O_2^{2-}$

If $P$ to $T$ are second period $p-$block elements,then which of the following graphs shows the correct relation between the number of valence electrons in $P_2$ to $T_2$ (corresponding molecules) and their bond order?