Nature of C-X bond in haloarenes

The $\mathrm{C}-\mathrm{X}$ bond of haloarenes is shorter than in haloalkanes. Explain. 

The $\mathrm{C}-\mathrm{X}$ bond in haloarenes acquires a partial double bond character due to 

$\mathrm{C}-\mathrm{Cl}$ bond in chlorobenzene in comparison to $\mathrm{C}-\mathrm{Cl}$ bond in methyl chloride is

The weakest $\mathrm{C}-\mathrm{Cl}$ bond is present in

Explain the nature of $\mathrm{C}-\mathrm{X}$ bond in: