信息系统的子系统划分属于系统开发的( )。
A．可行性分析阶段
B．逻辑设计阶段
C．物理设计阶段
D．系统实施阶段
参考答案：B
已知▱ABCD的两条对角线AC、BD互相垂直，且AC=6cm，BD=8cm，则边AB的长为______cm．
---I’ve just heard that the lecture (讲座)to be given by Ma Yun,the Alibaba CEO,has been cancelled(取消).
---Oh , no!_____________________________
A．It’s wonderful.
B．It doesn’t matter.
C．I have no idea.
D．I was looking forward to that.
