I know the federal number is 260, but some states have less.
I have no clue as we don't follow federal or state calendars at all. We are closed 3 days a year -- thanksgiving, Christmas and easter....
I do not understand either. No matter which state I am in at the moment, every day might be a day I perform work. If you are asking about some sort of governmental payroll, only said government can answer, since they usually have a way to make up at least some their own rules.
I have worked for two companies that had 9 paid holiday days if that helps.. Did not mean that some people did no have to work those days.