\textbf{125.} In the figure below, chord $AB$ equals the radius of the circle and $AB \parallel CD$, angle $\beta = 2\alpha$, and $CX$ is tangent to the circle. How many degrees is $\widehat{BD}$?
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\textit{[Figure: Circle with chord AB equal to radius, AB$\parallel$CD, tangent CX, angles $\alpha$ and $\beta$ marked]}
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(1) $50$\\
(2) $60$\\
(3) $70$\\
(4) $75$
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