Identify the correct statement.

Given below are two statements $:$
Statement $I :$ Nitrogen forms oxides with $+1$ to $+5$ oxidation states due to the formation of $p\pi-p\pi$ bond with oxygen.
Statement $II :$ Nitrogen does not form halides with $+5$ oxidation state due to the absence of $d$-orbital in it.
In the light of given statements,choose the correct answer from the options given below.

The dimerisation of $NO_2$ is accompanied with

The oxides of nitrogen obtained by the reaction of nitric acid with $(i)$ $P_4O_{10}$ and $(ii)$ $P_4$ respectively are:

Which of the following compounds is the most acidic?

Which of the following oxides will not act as a reducing agent?