Noelle Geo DMG Bonus or DEF??

I wanna build hybrid noelle, with good healing but decent dps.

I think to build her with 2p set Arcaic Petra + 2p set Retracing Bolide.

is that good enough or any better suggestion? like full set Arcaic Petra or Retracing Bolide?

also is 4 p set from arcaic carried over other character?

and also, if i have 15% Geo DMG bonus, this DMG Bonus is calculated from what, base atk?

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