Answer:
19. C
20. D
21. B
22. A
Explanation:
If an angle is subtended from an arc and it goes to the opposite end of the circle, the angle is HALF of the measure of the arc. If it goes to the center, it is SAME measure as arc.
19.
Arc BC is DOUBLE of Angle BAC, so
78 * 2 = 156
Answer is C
20.
Arc BEC is DOUBLE of Angle BAC, so
114 * 2 = 228
Answer is D
21.
Angle ABC is HALF of Arc AC, so
Angle ABC = 110/2 = 55
Answer is B
22.
Angle ABC is HALF of Arc AC, so
Angle ABC = 218/2 = 109
Answer is A