URGENT!!! Topic is Algorithm

Reverse Dijkstra [15 points]: Dijkstra algorithm is used to greedily find the shortest paths from a chosen starting node to all other nodes in a graph a) Can we reconstruct the entire graph if we are given the output of Dijkstra algorithm for the graph? If yes, explain how? If no, explain why and provide a counter-example. (you can provide the counter-example graph in the form of adjacency lists) b) Assume we run different instances of the Dijkstra algorithm accepting a different node as the starting node in the graph in each run. Then, we combine the output of each run, how will our chance to construct the entire graph be affected? Explain