How many $(\sigma)$ and $(\pi)$ bonds are present in the structure of $DDT$ respectively?

Product $(s)$ formed during this reaction is/are

The reaction of toluene with $Cl_2$ in the presence of $FeCl_3$ gives $X$ and the reaction in the presence of light gives $Y.$ Thus,$X$ and $Y$ are

In the following reaction sequence,
$Br-CH_2-CH(Br)-Ph$ $\xrightarrow[2. NaNH_2]{1. Alc. KOH} X$ $\xrightarrow[4. Conc. HNO_3/H_2SO_4]{3. HgSO_4/dil. H_2SO_4, Heat} Y$
$X$ and $Y$ respectively are,

The correct order of increasing reactivity of $C-X$ bond towards nucleophile in the following compounds is:
$I$: Chlorobenzene (or aryl halide)
$II$: $2,4$-Dinitrochlorobenzene
$III$: $(CH_3)_3C-X$ ($3^o$ alkyl halide)
$IV$: $(CH_3)_2CH-X$ ($2^o$ alkyl halide)

Match the reactions given in Column-$I$ with the types of reactions given in Column-$II$.