An annulus is a shape made from two concentric circles. The diagram shows an annulus consisting of two concentric circles of radii 2 and 9. Inside this annulus two circles are drawn without overlapping, each being tangent to both of the concentric circles that makes the annulus.
In a different annulus made by concentric circles of radii 1 and 9, what would be the largest possible number of non-overlapping circles that could be drawn in this way?
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