Which compound is used as an explosive?

In which of the following molecules does electrophilic attack occur at the meta position?

The correct order of reactivity for the reaction involving the cleavage of the $C-X$ bond in the following compounds is:

The major product of the reaction is:

Which of the following sets of compounds is $NOT$ arranged in the order of decreasing reactivity towards electrophilic aromatic substitution?

Which of the following statements are correct?
$A$. The $C-Cl$ bond in chlorobenzene is shorter than in chloromethane.
$B$. It is more difficult to replace chlorine from chlorobenzene than from benzyl chloride.
$C$. The $C-Cl$ bond in chlorobenzene has some double bond character.
$D$. Chlorobenzene on chlorination gives $m$-dichlorobenzene.