属于非选择性钙拮抗药的是：
A．氟桂嗪
B．地尔硫草
C．硝苯地平
D．维拉帕米
E．尼莫地平
参考答案：A
已知目标计算机的IP地址却不知道其MAC地址时，应该通过哪个协议来解决？（）
A.IP
B.ARP
C.RARP
D.BOOTP
To secure a vessel in a particular place by means of chains or ropes made frast to the shore, to anchors, or to anchored mooring buoys, or to ride with both anchors down defines（）.
A.To moor
B.to berth
C.to anchor
D.to ride at anchor
