单项选择题内流河指由内陆山区降雨或高山融雪产生的、不能流入海洋、只能流入内陆湖泊或在内陆消失的河流。这类河流大多处于大陆腹地,远离海洋,得不到充足的水汽补给,干旱少雨,水量不丰。世界上最长的内流河是( )
单项选择题Suppose A, B, C are all matrices. Which of the following statements is true? A、If AB=0, then A=0 or B=0. B、If AB=AC, then B=C. C、 D、If A and B are invertible, then