All nodes have multiple connections to the network.
At least some nodes have multiple connections to the network.
Any node can be taken down without affecting network performance.
Network performance will be similar, no matter what kind of link is used between nodes.
A school district
A regional charitable organization
A regional power company
A local chain of grocers
Performance for all locations on the WAN would suffer.
The failed location would be unable to transmit or receive data, but other locations could communicate without a problem.
Data would no longer be transmitted to or from any of the locations.
The failed location would broadcast errors to every other location.
Here's an interesting quiz for you.