通常情况下，（）是责任保险承保的主要民事责任。 A.侵权责任 B.违约责任 C.无过

下图中每条食物链的起点生物都是

 

A．草　　

B．鹰　　

C．蛇　

D．兔

应用吗啡或芬太尼复合全麻后，拔管指征是()

A．咳嗽反射存在

B．呼吸>12次/分，潮气量正常

C．自主呼吸恢复，Sp0>95%

D．意识恢复

E．对疼痛刺激有反应

In low - speed network ,it is usually adequate to wait for congestion to occur and then react to it by telling the source of packets to slow down. In high - speed networks, this approach often works poorly, because in the (71) between sending the notification and notification arriving at the source, thousands of additional (72) may arrive. In ATM network , a major tool for preventing (73) is (74) control. When a host wants a new virtual (75) ,it must describe the traffic to be offered and the service expected.

A．packets

B．cells

C．message

D．files

农家书屋管理和服务模式是什么？

为了满足子网寻径的需要，路由表中不包含的元素是？（）

A.子网掩码

B.源地址

C.目的地址

D.下一跳地址