Question 1114906
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Angle ACB with measure 35 degrees has its vertex on the circle, so the measure of arc ACB is 2*35 = 70 degrees.<br>
It is given that arc AEC measures 278 degrees, so the measure of arc EFA is 278-70 = 208 degrees.<br>
Arc EFA is the arc cut off by angle ACE, so the measure of angle ACE is 208/2 = 104 degrees.