Answer: A) arc CB = 120°
C) <COB = 2(m<CAB)
D) <COB = 120°
Explanation:
The measure of an inscribed angle is half the measure of its intercepted arc
⇆ The measure of an arc is twice the measure of its inscribed angle.
Thus, since <CAB = 60°, then arc CB = 120° OPTION A
The measure of a central angle is congruent to its arc
⇆ The measure of an arc is congruent to the central angle.
Thus, since arc CB = 120°, then <COB = 120° OPTION D
Since <COB = 120°, and <CAB = 60°,
then <COB = 2(m<CAB) OPTION C