Answer and explain this question from Algorithm Design and Analysis class. Thanks

Question 2. i) Consider an undirected graph of n nodes. What is the maximum possible number of edges in the graph? ii) Calculate the number of edges in a complete undirected graph of n nodes. iii Consider a directed graph of n nodes. What is the maximum possible number of directed edges in the graph? Question 3. (i) Write a technique to test if a connected graph is a tree. ii Considering the graph as the input, what is the time complexity (using big O- notation) of the above technique of tree testing? Explain your answer. iii Write a technique to test if a connected graph has any cycle or not