CEMC Pascal, 1999

Geometry Difficulty 1.0 Junior Find the answer Canada

In the diagram, a circle is divided by lines through its centre into four regions with angles $110°$ , $a°$ , $b°$ , and $60°$ marked, where $a°$ and $b°$ are adjacent to each other and to the $110°$ and $60°$ angles respectively. The value of $a+b$ equals

(A) $10$ (B) $85$ (C) $110$ (D) $170$ (E) $190$

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