Help me pls I need this answer

Answer:
Assuming that [tex] \overline{AOC} [/tex] is a diameter.
Given that [tex] m\angle{BAC} \: = \: 66° [/tex]
And that point O is the center of the circle
[tex] \boxed{m\angle{BAC} \: = \: 57°} [/tex]
Explanation:
Because angle AOB is subtended by arc AB from point O.
Arc AB is equal to the measure of that angle.
Since arc ABC is subtended by the diameter, the arc is 180°.