超声诊断右室双出口哪一项是错误的（）
A.主动脉骑跨<50%
B.右室壁增厚
C.右室增大
D.主动脉骑跨>70%
E.室间隔缺损
参考答案：A
Though she talks ____,she has made _____ friends here.
A．a little, a few
B．little,few
C．little,a few
D．few,a few
当电子层作为最外层时，最多容纳8个电子；当它作为次外层时，最多容纳18个电子。该电子层可能是 [ ]
A．K层
B．M层
C．L层
D．N层
