Concept:Use alternate angles and the angle sum on a straight line to find the unknown angle.Explanation:∠EHI=40∘ is equal to ∠DEH=40∘ because they are alternate interior angles.It is given that ∠BEH=90∘.Therefore, ∠BED=90∘−40∘=50∘.Since ∠BED and ∠BEF lie on a straight line, their sum is 180∘.So, ∠BEF=180∘−50∘=130∘.Finally, ∠ABE=m is alternate to ∠BEF, so they are equal.Thus, m=130∘.
