Switching loop query

[Deman]

Hi, got a question that's been on my mind which I haven't quite been able to nut out. Switches, managed switches that is.

1. If you've got 2 managed switches linked together what would happen if you add an unmanaged switch in between them creating a loop (i.e two links between the 2 main switches, one is direct other contains an intermediary unmanaged switch).

2. You have an unmanaged switch connected to a managed but on that unmanaged you hook a cable between two of its ports creating a loop.

My suspicion is for in scenario 1 STP would block one of the ports preventing the loop. But for the other I'm not really sure what it would do. Whether STP can do anything or whether you have to configure another protocol to do so. From my recollection STP is supposed to prevent broadcast storms but I don't think/know if it can react to them.