1. An organization purchases a Class B address space and plans to use subnetting to assign addresses to its end nodes, which are actually spread across several physical networks. There are 30 networks, and the network with the largest number of hosts has 100 hosts. The administrator desires to use the same subnet mask in all routes of all internal routers if this is possible. (a) What are the possible subnet masks it could use? (b) Suppose it is known that one of the networks will later grow to 150 hosts. Which of the masks identified in part (a) will continue to work, and which will not