$(1)\,CH_3C \equiv C - CH_3$ $(2)\,CH_3CH_2 -CH_2 -CH_3$
$(3)\, CH_3CH_2C \equiv CH$ $(4)\, CH_3CH = CH_2$



$\begin{array}{*{20}{c}}
{C{H_3}\,\,\,\,\,\,\,\,\,} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{C{H_3} - CH - C = CH}
\end{array}\xrightarrow[{{H_2}O}]{{HgS{O_4},{H_2}S{O_4}}}X$ $\xrightarrow[{(ii)\,conc.{H_2}S{O_4}/\Delta }]{{(i)\,{C_2}{H_5}MgBr,{H_2}O}}Y$
નીપજ $(B)$ નું બંધારણ શું હશે ?