The arrangement of the following compounds in the increasing order of their boiling points is:
$i$. bromomethane
$ii$. bromoform
$iii$. chloromethane
$iv$. dibromomethane

Match the $LIST$-$I$ with $LIST$-$II$:

List-$I$ (Reaction)	List-$II$ (Mechanism)
$A$. Williamson Synthesis	$I$. Electrophilic addition
$B$. Friedel-Crafts Reaction	$II$. Free radical substitution
$C$. Bromination of vinyl benzene	$III$. Nucleophilic substitution
$D$. Chlorination of toluene in light	$IV$. Electrophilic substitution

Choose the correct answer from the options given below:

Compound $C_4H_8Cl_2$ $(A)$ on hydrolysis gives a compound $C_4H_8O$ $(B)$ which reacts with hydroxylamine and does not give any test with Tollen's reagent. What are $(A)$ and $(B)$?

Given below are two statements $:$
Statement $(I) :$ $cis-1,2-dichloroethene$ is more polar than $cis-1,2-dibromoethene$.
Statement $(II) :$ Boiling point of $trans-1,2-dibromoethene$ is lower than $cis-1,2-dibromoethene$ but it is more polar than $cis-1,2-dibromoethene$.
In the light of the above statements,choose the most appropriate answer from the options given below $:$

Which compound undergoes nucleophilic substitution with $NaCN$ at the fastest rate?

For a given alkyl group,the densities of the halides follow the order: