What are two reasons to implement H·323 gatekeepers?() [" to eliminate the need for VoIP gateways"," to scale a VoIP installation with multiple gateways"," to provide call admission control and limit the number of simultaneous calls on the network "," to meet the requirement to control H·323 gateways on a LAN"," to accept call requests and reduce the load on the gateway"]
教育实验设计的主要内容包括() ["研究假设","自变量、因变量、控制变量","实验处理","以上都是"]
单音节词就是由一个语素构成的词。
观察者在看到闪电后5.5秒钟听到雷声,求打雷处与观察者之间的距离?
在不确定因素情况下,进行本量利分析时,各种有关因素的值是一个()。
使动用法:动词和宾语的关系,需要用()的语言形式去理解或者音译,使动用法中的谓语动词,有的原来就是(),有的是由()、()活用为动词的。