26. 55 degrees, as 360-125-125 = 110. Divide in half to get on part of the arc.
28. Arc CB is congruent to Arc BD; In the same or congruent circles, congruent chords have congruent arcs.
Arc AD is congruent to Arc AC; In the same or congruent circles, congruent arcs have congruent chords.
AB bisects the chord and all respective arcs. A diameter that is perpendicular to a chord bisects the chord and its two arcs.
30. CP and CQ bisect their respective arcs and chords they are perpendicular to; A line that passes through the center of a circle and is perpendicular to a chord in that circle also bisects the chord and its arc.