Answer:
m(arc EFD) = 270°
Step-by-step explanation:
m(arc EFD) = m(arc EF) + m(arc FD)
Since, m(arc EF) = Angle subtended by the arc EF at the center
= 146°
m(arc DE) = 90°
And sum of all the angles subtended by the arcs at the center = 360°
m(arc EF) + m(arc FD) + m(arc DE) = 360°
146° + m(arc FD) + 90° = 360°
m(arc FD) = 360° - 236°
m(arc FD) = 124°
Therefore, m(arc EFD) = m(arc EF) + m(arc FD)
= 146 + 124
= 270°
