Identify reagent $B$ in the following reaction: $R - X \xrightarrow{B} \text{Nitroalkane}$

Which of the following alkyl halides is the fastest to undergo dehydrohalogenation with a base?

The reaction of vinyl chloride with $HCl$ yields ...... .

In which of the following reactions does an $SN^1$ reaction take place?

Consider the following reaction sequence:
$Cyclohexylidene-methane$ $\xrightarrow[CH_3OH]{Br_2} A$ $\xrightarrow{KCN} B$
Identify the correct structures for $A$ and $B$ from the given options:
$A$ is:
$A) \text{ 1-(bromomethyl)-1-methoxycyclohexane}$
$B) \text{ 1-(methoxymethyl)-1-bromocyclohexane}$
$B$ is:
$C) \text{ 1-(bromomethyl)-1-methoxycyclohexane}$
$D) \text{ 1-(cyanomethyl)-1-methoxycyclohexane}$

Number of moles of $CH_3MgBr$ consumed in the above reaction is: