please do part a and b

(10 points) Use the Dijkstra's algorithm with a priority queue implemented as an unsorted array to find kgtra's Algorithm the shortest path from the vertex A to all vertices in this graph below. D I ch iteration, illustrate the priority queue with information about a current value of the shortest path and a vertex parent on a path from the vertex A ? (b) Draw the shortest path tree returned by this algorithm. (c) Explain why the Dijkstra's algorithm is classified as a greedy algorithm? When does it generate a correct output? (d) What is an efficient running time of the Dijkstra's algorithm for a dense graph? Specity a repreen- tation of a graph and minimum priority queue supported by the decrease_ key operation