$\rightarrow 10\, \pi\, {e}^{-}$in cyclic conjugation

$\rightarrow \text { Aromatic }$

$(2)$ $\rightarrow 4 \pi {e}^{-}$in ring conjugation $\Rightarrow$ Anti Aromatic

$(3) \Rightarrow 4 \pi {e}^{-}$in ring conjugation $\Rightarrow$ Anti Aromatic

$(4)$  $\Rightarrow 6 \pi {e}^{-}$in ring conjugation $\Rightarrow$ Aromatic

- Cyclopentadienyl anion