Answer:
option B 70° is the answer.
Step-by-step explanation:
It is given in a circle with center O.
measure of arc AB = measure of arc CD
(Since both the arcs are congruent)
∠AOB = 70°
so m(arc AB) = 70°
since m(arc AB) = m (arc CD)
So m(arc CD) = 70°
and angle formed at the centre by arc DC = 70°
Therefore, option B 70° is the answer.
