$1$-Bromo-$3$-chloro cyclobutane will react with two moles of $\mathrm{Na}$ in ether producing:

The correct statement about the following compounds

 is:

By Swarts reaction, the total number of alkyl halides that can be obtained from the following options will be: _____

Chlorobenzene, tert-butyl iodide, methyl fluoride, ethyl chloride, propyl fluoride, methyl iodide and $1$-bromo-$2,2$-dimethylpropane.

$\mathrm{R}-2-$ chloropentane $\underset{{\mathrm{Cl}}_2}{\overset{\mathrm{hv}}{\to }}$ Monochlorination takes place.

The total number of monochlorinated products formed in the above reaction is $\mathrm{x}$. Find the value of $\mathrm{x}$

In ${\mathrm{S}}_{\mathrm{N}}1$ reaction, the racemisation takes place. It is due to: