Geometry

Question Analysis:
This question involves equilateral and right triangles.
The main focus is on using angle properties of an equilateral triangle and right triangles to find unknown angles.

Key Concept Explanation:
Equilateral Triangle Property:
An equilateral triangle has three equal angles, each measuring 60°.
Right Triangle Property:
A right triangle has one 90° angle, and the sum of the other two angles must be 90°.

Step-by-Step Solution:  
Step 1: Find  
- Since the upper triangle is equilateral, all its angles are 60°.  
- The angle adjacent to (which is part of the equilateral triangle) is 60°.  
- Since the given diagram contains a right angle next to , we use:  
   
Step 2: Find  
- The right triangle contains a 90° angle.  
- Since we just found that , the remaining angle is:  
   
Thus, we get

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