If all the nucleophilic substitution reactions at saturated carbon atoms in the above sequence of reactions follow $S_N2$ mechanism, then $\underline{E}$ and $\underline{E}$ will be respectively,

The reaction of $4-methylcyclohexyl$ halide with $OH^-$ via the $S_N2$ mechanism produces $A$. Identify $A$.

What is the bond length between carbon and bromine in $CH_3Br$ molecule (in $pm$)?

The reaction of $4-$bromobenzyl chloride with sodium cyanide in ethanol leads to the formation of

Arrange the following compounds in decreasing order of reactivity for nucleophilic substitution reaction:
$(I)$ $CH_3-CH_2-OSO_2CF_3$
$(II)$ $CH_3-CH_2-OTs$
$(III)$ $CH_3-CH(OH)-CH_3$
$(IV)$ $C_6H_5-CH(OH)-CH_3$

In a nucleophilic substitution reaction,the order of halogens as incoming (attacking) nucleophiles is: $I^{-} > Br^{-} > Cl^{-}$. The order of halogens as departing (leaving) nucleophiles should be: