题目

如图，已知A地在B地正南方3千米处，甲乙两人同时分别从A，B两地向正北方向匀速直行，他们与A地的距离s(千米)与所行的时间t(小时)之间的函数关系图象用如图所示的AC和BD表示，当他们行走3小时后，他们之间的距离为_____千米．   答案：_1.5__() 25. Has David his hometown since he ?   A. been away; has been married   B. been away from; got married   C. been away from; has been married   D. left; got married