1 Yes, use BAT, either lines or phone all details, play around with it and see what works best for you
2 Google "show risdb query phones" that's the closest thing you can get
3 No such report.
If you're trying to find devices which have not been "used" (ie made/received calls) if CAR/CDR is enabled you can generate the reports for a certain period of time, you'll see devices which have been active during that period of time, and anything not showing calls, has not been active.
HTH
java
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