The table below shows the distances between eight cities are given as follows. Cities 1-2 1-3 2-3 2-6 2-7 3-4 3-5 3-6 4-5 5-6 5-8 6-7 6-8 7-8 Distances (km) 250 230 180 115 260 340 100 310 265 175 190 90 200 105 85 (a) Construct the network (b) Use Dijkstra's algorithm to find the shortest path from city 1 to city 8. (c) Use the algorithm for the minimum spanning tree problem to find the minimum path and its total length. Explain how the choice of the initial node can affect the result