请把下面语句工整规范地书写在下面的横线上。 流水不腐，户枢不蠹。 _______

One ofthe main resposibilities ofICMP is to report  （） . Although technology hasproduced increasingly relaible transmission media, errors still exist and must be handled. IP isan  （）  protocol. This means that error checking and error control are not a concem ofIP. ICMP was designed, in part, to compensate for this shortcoming. Howerver, ICMP doesnot  （） errors, it simply report them. Error correction is left to the higher-levelpotocols. Error messages are always sent to the original  （）  because the only informationavailable in the datagram about the route is the source and destination IP addresses. ICMP usethe source IP address to sent the error massage to the source ofthe（）.

IP isan（）protocol.

A．reliable

B．unreliable

C．available

D．unavailable

有关变异性心绞痛，描述正确的是（）

A.有关导联的ST段抬高

B.有关导联的ST段下移

C.心电图无变化

D.有关导联T波倒置

E.有关导联有异常Q波

疯油膏功效与作用

工资支付办法有哪些？

对于某台主机来说，除了需要进行IP地址和IP地址掩码的设置外，还需设置至少一台路由器的IP地址作为【 】， 以使该主机能够访问其他网段的主机。