AB \equal{} AC, \angle BAC \equal{} 80^\circ. Let E be a point inside △ABC such that AE \equal{} EC and \angle EAC \equal{} 10^\circ. What is the measure of ∠EBC?<spanclass=′latex−bold′>(A)</span>10∘<spanclass=′latex−bold′>(B)</span>15∘<spanclass=′latex−bold′>(C)</span>20∘<spanclass=′latex−bold′>(D)</span>25∘<spanclass=′latex−bold′>(E)</span>30∘