下列哪个天线不可以用作室内覆盖场景（）
A.壁挂天线
B.八木天线
C.智能天线
D.吸顶天线
参考答案：C
若关于x的一元二次方程kx2-6x+1=0有两个不相等的实数根，则k的取值范围是______．
Pericardiocentesis is performed on a client with cardiac tamponade. This procedure would be deemed effective if
A．aspirated blood clots rapidly.
B．blood pressure decreases.
C．blood pressure increases.
D．heart sounds become muffled.
