9514 1404 393
Answer:
40°
Step-by-step explanation:
The sum of arcs of a circle is 360°, so the measure of arc CD is ...
CB +BD +CD = 360°
CD = 360° -140° -140° = 80°
The measure of inscribed angle B is half the measure of the arc it subtends:
∠B = arc CD/2 = 80°/2
∠B = 40°
