Answer:
m∠A ≈ 103°
Explanation:
Enough information is shown for us to be able to use the Law of Sines to find the angle. That tells us ...
sin(A)/a = sin(C)/c
A = arcsin(a/c·sin(C)) = arcsin(26/6·sin(13°)) = arcsin(0.974788)
A = 77.1° or 102.9°
The claim is that the figure is drawn to scale, so we can assume that A is an obtuse angle:
m∠A ≈ 103°
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Additional comment
The sum of angles A and B must be 180° -13° = 167°. Since angle A is the largest, it must be more than half this value, or more than 83.5°. That means, we must choose the obtuse angle for A, rather than the acute angle.