题目

已知线段AB＝4，在直线AB上取点C，使BC＝6，若点D是线段AC的中点，则AD的长为 ． 答案：【1】5或119、—Bob! Is this your dictionary? —No, it isn’t．Ask Sally．She is looking for_______. A．his          B．hers           C．mine         D．yours