$4.$ A computer on a LAN is not able to connect to the Internet even though other computers on the LAN are able to connect. You use the ipconfig command to discover the IP address of the computer is $169\mathrm{.}254\mathrm{.}18\mathrm{.}45.$ What can you conclude from this information? $$The ISP connection is down, and you need to reboot the router. $$The computer did not connect to the router to receive a dynamic IP address. $$The computer's NIC is not functioning correctly, or a port on the router is bad. $$The router's DHCP server is not configured correctly.