The correct orders and statements for histidine are

Give the stability order in the following pairs.

Give the stability order in the following pairs:

Find the total number of carbons where the positive charge can be delocalized by true resonance [including the given
structure].

.

Find the total number of carbon where positive charge
Can be delocalised by true resonance [including the given
Structure].

Find the total number of the position where the positive charge can be delocalized by true resonance.

(Excluding the given position)

Find the number of carbon atoms including the given structure, which can have negative charge in resonating structures. (The structures with charge separation are
not acceptable.)

Identify the total number of compounds which contain equal $\mathrm{C}-\mathrm{O}$  bond length and explain why.

$\left(III\right)$ 

Explain:

Why benzyl carbocation is more stable than ethyl carbocation?