Let P Q R S be a square with side length 12. Point A lies on segment \overline{Q R} with \angle Q P A=30^{\circ}, and point B lies on segment \overline{P Q} with \angle S R B=60^{\circ}. What is A B?
Let P Q R S be a square with side length 12. Point A lies on segment \overline{Q R} with \angle Q P A=30^{\circ}, and point B lies on segment \overline{P Q} with \angle S R B=60^{\circ}. What is A B?