3. Given a trapezoid (not a parallelogram) $A B C D$. It is known that triangles $A B D$ and $C B D$ are isosceles, and angle $A$ is 36 degrees. Find all possible values of angle $C$ and list them in ascending order separated by a semicolon.
Answer: $54 ; 72 ; 108 \mid 54,72,108$

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