Hi efx, 

This is a fairly straightforward interview exercise which I have seen and even done a few in my time. However, you haven't actually asked a question about it in your forum post. So can I ask why have you actually posted it? Do you want help answering it or are you giving it as an example of what you could be asked during an interview (in which case it may be better off in the 'Interview Questions' section. 

Whoever wrote this use case clearly has no idea what a use case is.

Looks like system design to me. The so called requirements are just program specs.

To paraphrase the 3 amigos who formalised use cases back in the 90s, a use case describes the interactions of an actor with a system that results in a goal that is of benefit to that actor. By definition the system itself doesn't initiate anything. (pretty loose paraphrase). 

There is generally a main course with any alternates. pre and post conditions.

often described:

actor does x

system responds with y

actor does z

system responds with a.

etc.

Having said that, the 3 amigos didn't provide a definition of how a use case is described.

Anyway, don't expect anyone cares much cause this approach seems to be everywhere nowadays. I always found that if I didn't consider the business requirements first (there are none in this example), then inevitably I made assumptions that often proved false.

So there,

Kimbo