题目

如图，在△ABC中，AB＝BC，∠B＝120º，AB的垂直平分线交AC于点D．若AC＝6cm，则AD＝     __________cm．  答案：2解析:略 ________ for his expert advice, he was able to help a great number of people with their personal affairs. [　　] A．Being known B．Having known C．Well known D．Knowing