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UKMT Junior Mathematical Challenge, 2023

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

What is the sum of the four marked angles in the diagram? The diagram shows several lines crossing each other with four angles marked (shaded) at various intersection points.

(A) $540^\circ$ (B) $560^\circ$ (C) $570^\circ$ (D) $600^\circ$ (E) $720^\circ$

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