Nitrobenzene on nitration gives

Identify $Y$ in the following reaction.

The reaction of $2,6-$dideutero-fluorobenzene with $NaNH_2$ in liquid $NH_3$ gives:

The chemicals used for preparing acetophenone via Friedel-Crafts acylation are:
$(A)$ $C_6H_6$
$(B)$ $CH_3COCH_3$
$(C)$ $CH_3COCl$
$(D)$ Anhydrous $AlCl_3$

In which reaction does nitrobenzene give $o$- and $p$-substituted products?

Arrange the following groups in increasing order of reactivity towards electrophilic nitration reaction: $C_6H_6, C_6H_5Cl, C_6H_5COOH, C_6H_5NH_2$.