# Not enough lens

The final image $$I$$ of the object $$O$$ shown in the figure is formed at a point $$20 \text{ cm}$$ below a thin biconcave lens, which is at a depth of $$65 \text{ cm}$$ from principal axis. From the given geometry, calculate the radius of curvature (in $$\text{cm}$$) of lens kept at $$A$$.

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