The hosts in Branch 2 on the 192.168.40.0/24 network need a DHCP server to obtain IP addresses. The DHCP server is located on R1, which is in a different subnet. DHCP requests are broadcast messages, and broadcasts do not cross routers by default. To forward these DHCP requests to the DHCP server, the ip helper-address command must be configured on the interface closest to the requesting hosts (in this case, R2's GigabitEthernet 0/2 interface). This ensures that DHCP requests from Branch 2's subnet are forwarded to the DHCP server on R1.