题目

  American cities are similar to other cities around the world. In every country cities reflect the values of the culture. Cities contain the very best aspects of a society: opportunities for education employment and entertainment. They also contain the very worst parts of a society: violent crime racial conflict and poverty. American cities are changing just as American society is changing.  After World War II city residents became wealthier more prosperous. They had more children. They needed more space. They move out of their apartments in the city to buy their own homes. They boug如图为钠元素的原子结构示意图，下列说法不正确的是（ ）A．钠原子核外有三个电子层B．钠原子在化学反应中易得到电子C．钠原子最外层电子数为1D．钠原子核外电子总数为11