Answer:
D. 280°
Step-by-step explanation:
The question lacks the required diagram. Find the diagram attached below.
From the diagram,
arc EAC = arc EAB + arc BC ... (1)
Note that arc EAB is the angle on the straight line EB and since sum of angle on a straight line is 180°, arc EAB = 180°
Next is to get the arc BC. It can be seen from the diagram that arc BC + arc CD + arc DE = 180°
Given arc CD = 25°, arc DE = arc AB = 55° (since the diameter AD and BE are the same). On substituting this values we will have:
arc BC + 25°+55° = 180°
arc BC = 180° - 80°
arc BC = 100°
Remember from initial equation 1 that arc EAC = arc EAB + arc BC
arc EAC = 180°+100°
arc EAC = 280°
The measure of EAC is therefore 280°
