Which of the following is complex :

$(i)$ $\begin{array}{*{20}{c}}
{\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}-CH_2} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,|}
\end{array}} \\
{C{H_3} - {C^ + }} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}}
\end{array}$

$(ii)$ $\begin{array}{*{20}{c}}
{\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,|}
\end{array}} \\
{C{H_3} - {C^ + }} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{H}}
\end{array}$

$(iii)$ $\begin{array}{*{20}{c}}
{\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,|}
\end{array}} \\
{C{H_3} - {C^ + }} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}}
\end{array}$

$(iv)$ $Ph - CH ^{+}-\underline{ CH }_{3}$

→

The equilibrium constant for the reaction ${N_{2(g)}} + {O_{2(g)}}$ $\rightleftharpoons$ $2N{O_{(g)}}$ at temperature $T$ is $4 \times {10^{ - 4}}$. The value of ${K_c}$ for the reaction $N{O_{(g)}}$ $\rightleftharpoons$ $\frac{1}{2}{N_{2(g)}} + \frac{1}{2}{O_{2(g)}}$ at the same temperature is

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In the conversion of $N_2$ into $N_2^+$ the electron will be lost from which of the following molecular orbital ?

→

$IUPAC$ name of following compound is