Points A and B are at oppositive ends of a circular pond with diameter d. A bridge connects point A with point C, and another bridge connects point C with point B. The two bridges are of equal lenght. What is the ratio of the distance from A to B when traveling along the two bridges to the distance when traveling along the edge of the pond?
$$A.\ \ \frac{2\cdot\sqrt{2}}{\pi}$$
$$B.\ \ \frac{d\cdot\sqrt{2}}{\pi}$$
$$C.\ \ \frac{2}{\pi}$$
$$D.\ \ \frac{\sqrt{2}}{2\cdot\pi}$$
$$E.\ \ \frac{2\cdot\sqrt{2}}{d\cdot\pi}$$
The OA is A.
Experts, I need your help with this PS question. I don't know how can I solve this question. I think that I can get two right triangles with the points ACO and BCO but I don't know what can I do with it later. Thanks in advance!
