${({C_6}{H_5})_3}\dot C\, > \,{({C_6}{H_5})_2}\dot CH\, > \,{(C{H_3})_3}\dot C\, > \,{(C{H_3})_2}\dot CH$
The stabilisation of first two is due to resonance and last two is due to inductive effect.

$(I)$ $CH_2 = CH - C \equiv CH$
$(II)$ $CH \equiv C - C\equiv CH$
$(III)$ $CH_3 - CH = CH_2$
$(IV) $ $CH_2 = CH - C = CH_2$



$(x)\begin{array}{*{20}{c}}
{O\,\,\,}\\
{||\,\,\,}\\
{C{H_3} - S - O - H}\\
{||\,\,\,\,}\\
{O\,\,\,\,}
\end{array}$
$\begin{array}{*{20}{c}}
{\,\,\,\,\,O}\\
{\,\,\,\,\,\,||}\\
{(y)\,\,\,C{H_3} - C - O - H}
\end{array}$
$(z)\,\, CH_3 -OH$
