CEMC Euclid, 2007

Geometry Difficulty 2.0 Junior Prove it Canada

The Little Prince lives on a spherical planet which has a radius of 24 km and centre $O$ . He hovers in a helicopter ( $H$ ) at a height of 2 km above the surface of the planet. From his position in the helicopter, what is the distance, in kilometres, to the furthest point on the surface of the planet that he can see?

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