Which of the following reagents cannot be used in a Friedel-Crafts reaction?

The alkyl halide that does not give a white precipitate with alcoholic $AgNO_3$ solution is ................. .

Which of the following groups is an ortho and para directing group?

What is the product $X$ in the following Wurtz-Fittig reaction?

Among the following,the reaction that proceeds through an electrophilic substitution is

Arrange the following compounds in decreasing order of their rate of $S_NAr$ reaction:
$(i)$ $p$-nitrochlorobenzene
(ii) $m$-nitrochlorobenzene
(iii) $2,4$-dinitrochlorobenzene
(iv) chlorobenzene
$(v)$ $2,4,6$-trinitrochlorobenzene