The most reactive chlorine towards ${\mathrm{H}}_2\mathrm{O}$ is:

When the concentration of alkyl halide is tripled and the concentration of $\mathrm{O}\stackrel{⊝}{\mathrm{H}}$ ion is reduced to half, the rate of ${\mathrm{S}}_{\mathrm{N}}2$ reaction increases by $\mathrm{X}$ times. Report your answer as $10\mathrm{X}$.

The number of times where ${\mathrm{S}}_{\mathrm{N}}2$ reaction taken place in above reaction sequence is:

Among the $6$ how many cyclic isomers of molecular formula ${\mathrm{C}}_7{\mathrm{H}}_{13}\mathrm{Br}$ can form $1-$methylcyclohexane$-1-$ol on reaction with ${\mathrm{H}}_2\mathrm{O}/\mathrm{acetone}/{\mathrm{Ag}}^{+}$?

The relative rate of acid catalysed dehydration of following alcohols would be:

(I) 

(II) 

(III) 

(IV)