Which of the following reactants is used to obtain the compound $(A)$ shown below? (Assume that $EtO^{-}$ is used in all the reactions)

Identify the correct order of reactivity for the $E_2$ reaction with alcoholic $KOH$ for the following compounds:
$(i)$ $(CH_3)_3C-Cl$
(ii) $(CD_3)_3C-Cl$
(iii) $(CT_3)_3C-Cl$

Predict the order of reactivity of the following compounds in $S_N1$ reaction :
$(I)$ $CH_3-CH_2-CH(Br)-CH_3$
$(II)$ $(CH_3)_2CH-CH_2-Br$
$(III)$ $(CH_3)_3CBr$

Which of the following statements is incorrect for a bimolecular nucleophilic substitution reaction $(S_{N}2)$?

An isomer of $C_3H_6Cl_2$ on boiling with aqueous $KOH$ gives acetone. Hence,the isomer is

What is the correct order of reactivity of halides for the $S_{N}2$ reaction?