Which among the following has the highest boiling point?

$CCl_4 + KOH$ (excess) $\rightarrow$ end product of the reaction is :

The relative reactivity of the following halides toward $S_{N}2$ reaction follows the order:
$(P)$ $CH_2=CH-Cl$
$(Q)$ $CH_3-CH_2-Cl$
$(R)$ $CH_3-O-CH_2-CH_2-Cl$
$(S)$ $C_6H_5-CH_2-Cl$

When $2-$Chlorobutane is boiled with a concentrated alcoholic solution of $KOH$,the major product formed is:

Arrange the following bromides in the order of reactivity in undergoing $S_{N}1$ reaction:
$(i)$ $(CH_3)_3CBr$
(ii) $CH_3CH_2CH_2Br$
(iii) $(CH_3)_2CHCH_2Br$
(iv) $CH_3Br$

The reaction $Ph-CH_2-CH(F)-CH_3 \xrightarrow[EtOH]{KOH} X$. What is $X$?