$4\mathrm{.}4\mathrm{.}5$ Change the direction of edge $02$ in tinyEWD.txt $($see page $644).$ Draw two different SPTs that are rooted at $2$ for this modified edge$-$weighted digraph.

$4\mathrm{.}4\mathrm{.}6$ Give a trace that shows the process of computing the SPT of the digraph defined in Exercise $4\mathrm{.}4\mathrm{.}5$ with the eager version of Dijkstra's algorithm.

$4\mathrm{.}4\mathrm{.}13$ Show, in the style of the trace in the text, the process of computing the SPT with Dijkstra's algorithm for the digraph obtained by removing the edge $5->7$ from tinyEWD.txt $($see page $644).$

$4\mathrm{.}4\mathrm{.}21$ Show, in the style of the trace in the text, the process of computing the SPT with the Bellman$-$ Ford algorithm for the edge$-$weighted digraph of Exercise $4\mathrm{.}4\mathrm{.}5.$

$644$ CHAPTER $4=$ Graphs