题目

如图，AB∥CD，AD与BC相交于点O，若AO=2，DO=4，BO=2.5，则CO=_______ 答案：【答案】5【解析】由平行线分线段成比例定理，得到=；利用AO、BO、DO的长度，求出CO的长度．解：∵AB∥CD，∴=；∵AO=2，DO=4，BO=2.5，∴=，∴CO=5.故答案为：5.Hi！Amy, you didn’t come to my party last night, I just wonder ______last night.A. Where are you       B. where you are C. where were you      D where you were