In the following figure, there is an isosceles triangle in an equilateral triangle, and if angle 1 equals angle 2 and angle 3 equals angle 4, then angle 5 equals?  

In the following figure, there is an isosceles triangle in an equilateral triangle, and if angle 1 equals angle 2 and angle 3 equals angle 4, then angle 5 equals?  

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