#$3)15\mathrm{.}5\mathrm{.}4$ Describe the meaning of the graphical conventions used in

Figures $15\mathrm{.}3\mathrm{.}2$ through $15\mathrm{.}3\mathrm{.}4,$ illustrating Kruskal's algorithm. What do thick lines and

dashed lines signify?

Figure $15\mathrm{.}3\mathrm{.}2$: Example of an execution of Kruskal's MST algorithm on a graph with integer weights. We

Figure $15\mathrm{.}3\mathrm{.}3$: An example of an execution of Kruskal's MST algorithm $($continued$).$ Rejected edges are

show the clusters as shaded regions, and we highlight the edge being considered in each iteration

$($continued in ficu$$re helow$)$

$($g$)$

$($i$)$

$($e$)$

$($f$)$

Figure $15\mathrm{.}3\mathrm{.}4$: Example of an execution of Kruskal's MST algorithm $($continued from previous figures$).$

The edge considered in $($n$)$ merges the last two clusters, which concludes this execution of Kruskal's

algorithm.