If I am a salary worker and only worked one day out of that week, do I get paid for the whole week?

First its not a good idea to piggyback your question on someone else's. This can lead to confusion. You should start a new thread. So I've moved your question to its own thread.

No, even as a salaried employee you do not have to be paid for full days that you don't work. Of course there can be other policies involved here.

Not unless you have paid time off ( vacation, sick days or so forth) that you can use.

In days long gone, that was how it worked now the most you can expect from most are full pay for a day you report

If you only came to work one day that week, no, you would not be getting the full week's pay but just that one day pay. The part about getting paid for the full week comes into play when you have a company declared holiday, a paid leave of absence, or jury duty, or vacation days. If you just showed up one day you aren't entitled to the entire week's pay. Sorry.