How can black holes have electrical charge, and spin?

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Lamdbaenergy
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If the star's mass supposedly collapses into a single point, and it ends up having "said" zero volume, then how can people say that the hole has a specific spin or that it can have an angular momentum?

Does it mean that the singularity is somehow still spinning, or maybe the spacetime around it is just being dragged for some reason?
This subject has been confusing me quite a bit whenever I think about it.
 
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Lamdbaenergy said:
If the star's mass supposedly collapses into a single point, and it ends up having "said" zero volume, then how can people say that the hole has a specific spin or that it can have an angular momentum?

Does it mean that the singularity is somehow still spinning, or maybe the spacetime around it is just being dragged for some reason?
This subject has been confusing me quite a bit whenever I think about it.

Sometimes the BH's gravity field is referred to as a 'fossil' field-

http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/black_gravity.html
 
Turns out Kerr and Newman black holes do NOT contract into points. They contract to circles... which still have zero volume, because zero thickness throughout their nonzero circumference.
Reissner black holes are point charges, just like Schwarzschild black holes.
 
In short: the laws of conservation (angular momentum, charge, mass-energy, etc.) still work during the process of creation of a black hole. So if a star had some angular momentum/charge before it collapsed, the resulting black hole will also have some (assuming the angular momentum/charge was not radiated away during the collapse).

Also, the claim that black holes have "zero" volume is simply incorrect.