没人问过. 但是我想不通, 三角形在圆内, AB 是直径, 又知道比例, 怎么会求不出圆的周长呢?
Q20:
INE>INE>INE>INE> B
INE>INE> A C
In the figure shown, triangle ABC is inscribed in the circle. What is the circumference of the circle?
(1) AB is a diameter of the circle.
(2) The ratio of the lengths of BC, AC, and AB, respectively, is 3 : 4 : | 
