【单选题】The chapter ended with the hero in the precarious position of hanging from a cliff.
【单选题】()一般采用PCM作为传输手段,一般为PCM30/32。
【简答题】数字中继线一般采用( )作为传输手段,一般为( )。基群接口通常使用( )或( )传输信号,高次群接口逐步采用( )传输方式。
【单选题】The chapter ended with the hero in the precarious position of hanging from a cliff.