$($d$)$ Suppose that $H$ is a bipartite sub$($multi$)$graph of $G$ such that $V(H)=V(G)$ and that $v_1,v_2,v_3,v_4$ belong to

the same vertex partition. Let the edges of $G$ incident with $v_1,v_{2}in$ be labelled $e_1,e_2,e_3,$dots How many

labelled subgraphs $H$ exist such that $E(H)=\{e_1,e_2,e_3,$dots$\}?$