The document describes how to subnet the IP addresses 172.168.4.2/16 and 10.12.5.2/8. It identifies that 172.168.4.2/16 is a Class B network that can be divided into 16 subnets of 4096 IP addresses each using a subnet mask of 255.255.240.0. It also explains that 10.12.5.2/8 is a Class A network that can be divided into 16 subnets of 16 IP addresses each using a subnet mask of 255.255.255.240. Tables listing the network addresses and broadcast addresses of each subnet are provided.