In which of the following,the bond length between carbon and carbon atoms is equal?

What points should be kept in mind while drawing resonance structures?

Explain why $CO_3^{2-}$ ion cannot be represented by a single Lewis structure. How can it be best represented?

Consider the following three resonance structures:
The correct order of their stabilities is:

In a benzene molecule,all $C-C$ bond lengths are equal because:

Draw the possible resonance structures for $CH_3 - \ddot{O} - CH_2^+$ and predict which of the structures is more stable. Give reason for your answer.