CEMC Fermat, 2000

Geometry Difficulty 2.0 Junior Find the answer Canada

Three circles have centres $A$ , $B$ and $C$ with radii 2, 4 and 6 respectively. The circles are tangent to each other as shown. Triangle $ABC$ has

(A) $\angle A$ obtuse (B) $\angle B = 90°$ (C) $\angle A = 90°$ (D) all angles acute (E) $\angle B = \angle C$

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