1. Physical, Data Link, Network, Transport, Session, Presentation, Application
2. (a) The network layer. (b) The transport layer.
3. Class A: 10.0.0.0 to 10.255.255.255; Class B: 172.16.0.0 to 172.31.255.255; Class C: 192.168.0.0 to 192.168.255.255.
4. Unicast, broadcast, and multicast.
5. No (pfSense 2.4 and later will not run on 32-bit processors).
6. UFS and ZFS.
7. When the WAN interface has been configured, but the LAN interface has not yet been configured.
8. Configure a static IP address that is on the LAN network for the PC.
9. By navigating to System | Setup Wizard.
10. Because private networks should not be routed through the public Internet.