(1) As shown in Figure ②, it is known that at Rt△ABC, ∠ ACB = 90, ∠ ABC > ∠ A, CD is the center line on AB, the intersection point B is BE CD, and the vertical foot is E. Try to explain that E is the self-similarity point of △ABC;
(2) in △ABC, ∠ a < ∠ b < ∠ c 。
① As shown in Figure ③, use a ruler to make the self-similarity point P of △ABC (write out the practice and keep the drawing traces);
② If the internal P of △ABC is the self-similar point of the triangle, find the degrees of the three internal angles of the triangle.
Only problems.