CNT Books has expanded considerably since you first got the network up and running three years ago. It now occupies an entire floor in the building, and its LAN has grown to include several servers and more than 60 workstations. CNT Books has recently purchased another book company and needs more space and computers. Expansion plans include leasing another floor four stories up in the same building and adding 35 workstations and at least one more server immediately, with additional equipment purchases expected. What type of network is called for - LAN, WAN, MAN, or internetwork? What additional devices might be needed to ensure efficient network communication?