Can a registered nurse be salaried rather than paid hourly wages?

Sure they can; if you agree to a salary rather tha being paid hourly. Of course you should have a clear undesrtanding of the hours you will be expected to work for that salary and divide those by the salasry to find you general hourly wage. Salaried can be asked to come in at all hours andy days without additional compensation on the other hand; if your idea of your duties are conluded, you should be free to go home.
The concept of salary is that you have a given set of duties to be responsible for, inlcuding some supervision duties ( usually) and you are free to do them at your discretion. Though some people like a salary, because they hat ethe petty clocking in and clocking out; ten minute sthere; ten minutes here.

here is a rather long discussion on nurses and salaries in another question. after you read this, if you want to narrow your question I would try and help answer those questions.
http://www.webanswers.com/legal/labor-employment-law/is-it-legal-for-s ome-exempt-employees-nursing-supervisors-to-be-scheduled-to-work-holid ays-and-their-7445f4

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