Yes, we must switch to a WAN because each

LAN can only exist in a single physical location

using wires to join all the computers.

Yes, there is another option. We can just use

two separate LANs.

Switching to a WAN is the common way to

handle a remote location but there's another

way. We can use our current LAN as the hub

and the new site can connect to that.

Yes, we must use a WAN because no server can

handle two sites.