Select the correct statement(s) regarding ${\mathrm{N}}_3^{-}$ion 

${\mathrm{N}}_3^{-}$ has linear shape, its central nitrogen is sp-hybridised.and all All $d_{N-N}$ bonds are of equal length.

The hybridization is shown as,

$$\begin{gathered} \stackrel{\Theta }{N}=\stackrel{+}{N}=\stackrel{\Theta }{N} \\ sp \end{gathered}$$