Which of the following statement regarding nitric oxide is not correct

Question

$\begin{array}{1 1} \text{Nitric oxide dimerizes under ordinary conditions } \\ \text{The bond order of nitrosonium ion is 3} \\ \text{There is a decreases in nitrogen oxygen bond length in going from } No \;to\;No^{+} \\ \text{In nitrosyls nitric oxide is attached to the metal through nitrogen atom . } \end{array}$