维生素D缺乏性手足抽搐症患儿的主要护理诊断有____________和____________。
参考答案:有窒息的危险;有外伤的危险
如图所示,带电体Q靠近一个接地空腔导体,空腔里面无电荷,在静电平衡后,下列物理量中等于零的是( )
A.导体腔内任意点的场强
B.导体腔内任意点的电势
C.导体外表面的电荷量
D.导体腔内表面的电荷量
_____ the society developing very fast, it's quite necessary that we should have a good knowledge of
English and computers. [ ]
A. As
B. For
C. With
D. Since