I was scrolling though my e-mail from the debian user group and I saw
mention of pipewire, as a replacement for pulseaudio.  It seemed to
suggest that it was in Testing, so would not be available on my Devuan
Stable (chimaera) system, but I took a look, anyway.  It seems to be
available, and, in fact, installed on my system.  It seems to have been
brought in by zoom.

So my question are:

I have pipewire installed AND pulseaudio is still installed, as well. 
Don't they do the same thing?  Shouldn't they be conflicting with each
other?  My sound seems to be working fine. Is is using pulseaudio?  Or
is it using pipewire?

Is zoom using pipewire and everything else is using pulseaudio?

If pipewire is meant as a replacement for pulseaudio, can I delete
pulseaudio.  Will my sound, including upstream firefox, continue to work?

Marc