Shadow of a truncated paraboloid

A truncated paraboloid is given by

$z = x^2 + y^2 \text{, where } 0 \le z \le 4$

Its surface is made of an opaque material. It is lit by a single point omni-directional light source (omni-directional means radiating light in all directions).

Find the area of the shadow cast by the paraboloid on the $xy$ plane, due to the point light source which is positioned at $(3, 4, 5)$ ?

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