get partial credit if you show your work. If you make a mistake, it will also help the grader show you where you made a mistake. Quetsioni: short answer a. How the poisoned reverse solves the looping problem in distance vector algorithm b. Why is changing the IP layer of the Internet protocol stack hard? c. How/why do routing loops happen in the IP networks (give an example), and briefly describe how IP avoids the circulation of IP datagrams over such loops