The first one, may have two circles located on the circumference of the two circles stipulated depending on the location of circles A and B.
The second problem, the circle will lie on the perpendicular bisector of the lines between A and B and C and D, if they intersect, and they could be two different circle radii.
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So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates
-Dik