Find Angle between lines connected by red curve ?

ex11
Enter angle in degrees
°
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ex11
Enter angle in degrees
°
submit
ex11
Enter angle in degrees
°
submit
ex11
Enter angle in degrees
°
submit
ex11
Enter angle in degrees
°
submit
ex11
Enter angle in degrees
°
submit
ex11
Enter angle in degrees
°
submit
ex11
Enter angle in degrees
°
submit
ex11
Enter angle in degrees
°
submit
ex11
Enter angle in degrees
°
submit