$1.$ $\begin{array}{*{20}{c}}
{C{H_3}C{H_2}CHC{H_3}{\mkern 1mu} } \\
{{\mkern 1mu} \,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\,^ + }N{{(C{H_3})}_3}^ - OH}
\end{array}$ $\xrightarrow{{heat}}$ $\mathop {C{H_3}CH = CHC{H_3}}\limits_X $ $+$ $\mathop {C{H_3}C{H_2}CH = C{H_2}}\limits_Y $
$2.$ $\begin{array}{*{20}{c}}
{C{H_3}C{H_2}CHC{H_3}} \\
{\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,Br}
\end{array}$ $\xrightarrow{{heat}}$ $\mathop {C{H_3}CH = CHC{H_3}}\limits_X $ $+$ $\mathop {C{H_3}C{H_2}CH = C{H_2}}\limits_Y $
$(1)$ carbanion type transition therefore Hoffmann alkene is major. In reaction
$(2)$ alkene type transition therefore Saytzeff alkene is major .