Should I just apply to this other job?

I applied for about eight lifeguarding jobs this summer because I’d love to make some extra money for my trip to Argentina, but I haven’t heard back from a single one of them. I applied about two or three weeks ago, and I would think that they would have contacted me by now…
I have another job application at a library – which doesn’t pay as much but at least it’s a job.
Should I submit that application or wait a little while longer? The librarian in charge there already knows that I have the application and she signed and dated it so that she would remember that I was there as one of the first people (it was first come first serve).

And how long is the typical wait for a job response?