Which of the following statements regarding the structure aluminium chloride is correct?

All the bond lengths Cl-Al in ${\mathrm{Al}}_2{\mathrm{Cl}}_3$ are identical

All the bond lengths Cl-Al as well as all the bond angles Cl-Al-Cl and Al-Cl-Al are different

The bond lengths of terminal Al-Cl and bridged Al-Cl bonds are different and also outer bond angle Cl-Al-Cl and bridged bond angles Cl-Al-Cl and Al-Cl-Al have different values.

All the bond angles Cl-Al-Cl and Al-Cl-Al in ${\mathrm{Al}}_2{\mathrm{Cl}}_3$ are identical