题目

23. ________the warning message, more deaths would have been caused in the flood according to the report from Xinjiang. A. Regardless of    B. In spite of         C. But for            D. Thanks to 答案：C如图，将矩形纸片ABCD沿对角线AC折叠，使点B落到点B′的位置，AB′与CD交于点E．（1）试找出一个与△AED全等的三角形，并加以证明；（2）若AB=8，DE=3，P为线段AC上的任意一点，PG⊥AE于G，PH⊥EC于H，试求PG+PH的值，并说明理由．