题目

                  which school was suitable for their son, the parents visited lots of different primary schools    in the city. C.    Finding                  B. Being found                        C. Found                      D. To find 答案：D一副直角三角板如图放置，点A在DF的延长线上，BC∥DA，∠D=∠BAC=90°，∠C=45°，∠E=30°，AC=10．求BF的长．