<image>(2014 Autumn, Xishan District Midterm School Exam) Operation: Given a number line on a paper (as shown in the figure), fold the paper.  
(1) If the point representing 1 coincides with the point representing -1, then the point representing 6 coincides with the point representing ____.
(2) If the point representing -1 coincides with the point representing 3, answer the following questions:
① The point representing 6 coincides with the point representing ____.
② If the distance between points A and B on the number line is 12 (A is to the left of B), and points A and B coincide after folding, then the number represented by point A is ____.