4. Consider the directed graph shows in Figure 3. B A Figure 3: Directed graph (a) Draw the adjacency list representation of the graph. Assume that the first vertex inserted into the graph is A and in alphabetical order. (5 marks) (b) Construct the adjacency matrix for the graph. Assume that the first vertex inserted into the graph is A and in alphabetical order, (5 marks) (c) List the nodes in the order they would be visited in a depth-first search of the graph starting at vertex A. Show appropriate diagram on how the process is done. (10 marks)