In class, my professor only went over half wave, full wave and full wave bridge rectifiers. Looking at problem #1 on the homework, I don't know how to calculate the output voltage.
Pick one of them and show your best attempt to analyze it. We can then help you through that one and, armed with the knowledge gained, you can then attempt another. Probably after just one or two rounds you will be able to solve the rest on your own.
So for #1, would it even be considered a full wave rectifier? If it is, then the output voltage would be 0.9*Vrms. But with the 0.7V drop per diode, I'm not sure how to account for that.
Do not try to calculate the RMS value of the waveforms.
Just trace what is happening during a single cycle of the waveform and note the voltages at the points in the cycle where the diodes conduct and where they don't.
As Dodgydave noted, several of the circuits would fail in practice, thus are bad examples.
But I think your professor wants you to assume ideal components and ignore any possible failures.