SDH网管主要操作运行接口为Q3接口和F接口,其中Q3接口是具备()全部七层功能的接口。
参考答案:OSI
It was not until midnight ______ they reached the camp site. [ ]
A. that
B. when
C. while
D. as
风湿性心脏病最易累及的瓣膜是()
A.二尖瓣及三尖瓣
B.三尖瓣及肺动脉瓣
C.主动脉瓣及肺动脉瓣
D.二尖瓣及肺动脉瓣
E.二尖瓣及主动脉瓣