C A B D F E 1. What is the length of the shortest path from node E to node C? What is the shortest path(s)? 2. According to closeness measure, which node(s) is the most important node and what is its closeness value? Show the closeness adjacency matrix. 3. Which node is the most important node based on the node betweenness measure? 4. According to "acquaintance" measure, which node(s) is the best friend of B? Show all steps in computing the acquaintance values given B and his/her friends. 5. Write down the 4 steps of k-means clustering algorithm. List "4 weak points" of the K-means clustering algorithm.