下列图中具有稳定性是 （填序号）.
对不具稳定性的图形，请适当地添加线段，使之具有稳定性.
答案：具有稳定性的是1,4,6三个．
________ the girl is young , she can make money herself.
— The box is too heavy to carry. What's in it?
— Jack _______ it with many books.
下列哪个人物的事迹不会出现在《资治通鉴》中( )
