Which of the following IOS commands cause syslog messages to be stamped with time and dates？（） ["service timestamps log datetime","logging trap datetime","service logging datetime","logging datetime on","logging timestamps o"]
简述产生折射波的机制及条件，并说明什么是临界角。
VTP devices in a network track the VTP revision number. What is a VTP configuration revision number？（） ["A number for identifying changes to the network switch.","A number for identifying changes to the network router.","A number for identifying changes to the network topology.","None of the other alternatives apply."]
简单序列重复（SSR）是共显性分子标记，可区分纯合子和杂合子。
（）联合国第44届大会通过了《儿童权利公约》。 ["1959年11月20日","1989年11月20日","1990年8月29日","1992年4月1日"]
感觉信息加工
