$5.($a$)$ Consider the digraph $\backslash ($ G $\backslash )$ given in Fig. $(1$b$).$ Represent the digraph using adjacency matrix and adjacency lists. Assuming integers are of $4$ bytes, characters are of $1$ byte, and pointers are of $8$ bytes, calculated the amount of storage requirement in each representation.

$($b$)$ Consider the digraph $\backslash ($ G $\backslash )$ given in Fig. $(1$b$).$ Find the minimum spanning tree of $\backslash ($ G $\backslash )$ using Krushkal's algorithm. Depict the MST in conventional hierarchical tree representation $($like in Fig. $1$b$).$ What are the nodes in level$-2$ of the MST$?$ Show each step clearly.