Answer:
a=125°
Step-by-step explanation:
The angle at E=360-250=110°
Draw a horizontal through E, parallel to AB and CD such that it divides angle E into two angles of 55° each. Produce line AB to M such that the 55° at E is alternate with it.
A and 55° are now supplementary angles therefore
a+55°=180°
a=180-55=125°
