Explanation:
1) Angles opposite congruent sides in a triangle are congruent, so angle H is congruent to angle D.
2) For the same reason as the first problem, angle D is congruent to angle NSD.
3) Since sides opposite congruent angles in a triangle are congruent, segment AH is congruent to segment AS.
4) For the same reason as the third question, segment SA is congruent to segment SN.