As shown in figure ①, p is a point in △ABC, which connects PA, PB and PC. In △PAB, △PBC and △PAC, if there is a triangle similar to △ABC, then P is called the self-similarity point of △ABC.

(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.