Arrange the following in the increasing order of pKa values

The electron displacement effect observed in the given structures is known as

The number of activating and deactivating groups of the following are respectively

$$ \begin{aligned} & -\mathrm{OCH}_2 \mathrm{CH}_3,-\mathrm{COCH}_3,-\mathrm{NHCOCH}_3, \\ & -\mathrm{COOCH}_3, \mathrm{SO}_3 \mathrm{H} \end{aligned} $$

The delocalisation of $\sigma$ electrons of C-H bond of an alkyl group with the $\pi$ electrons of benzene is observed in