Answer:
 m = 39°
Explanation:
The useful relations here are ...
- the sum of angles in a triangle is 180°
 - inscribed angles subtending the same arc have the same measure.
 
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Angle ACB subtends the same arc (AB) as angle ADB, so has the same measure, 36°. Then the sum of angles in triangle ACB is ...
 33° +36° +72° +m = 180°
 m = 180° -141° = 39°