Given a situation: You have data about friend relationships from a social network, and you want to model the spread of a rumor based on these relationships. Your model is that a rumor starts with a single person, who then tells all of their friends. Then at each subsequent step, everyone who knows about the rumor spreads it to all of their friends who don't know it. What to do; you must select three answers:
-Specify the type of graph most appropriate for data in question in terms of un-directed or directed,
-Specify the type of graph most appropriate for un-weighted or weighted.
-Choose the graph algorithm that is best suited to computing a solution:
Breadth-First Search,
Minimum Spanning Tree (Prim's or Kruskal's),
Dijkstra's,
Depth-first search.
Breadth first search
Undirected graph
Unweighted
Weighted Dijkstra's

a  social news website  is an  internet  website  that features  user-posted stories. such stories are ranked based on popularity, as voted on by other users of the site or by website administrators. users typically comment online on the news posts and these comments may also be ranked in popularity. since their emergence with the birth of  web 2.0, social news sites have been used to link many types of information, including news, humor, support, and discussion. all such websites allow the users to submit content and each site differs in how the content is moderated. on the  slashdot  and  fark  websites,  administrators  decide which articles are selected for the front page. on  reddit  and  digg, the articles that get the most votes from the community of users will make it to the front page. many social news websites also feature an online comment system, where users discuss the issues raised in an article. some of these sites have also applied their voting system to the comments, so that the most popular comments are displayed first. some social news websites also have a  social networking  function, in that users can set up a user profile and follow other users' online activity on the website.