He didn't _______ a computer ten years ago. [ ]
A. had
B. have
C. has
答案:B
简述储户提前支取未到期的定期储蓄存款处理。
在实际的移动通信环境中,路径损耗与以下哪些因素有关()。
A.频率
B.传播距离
C.收发天线的高度
D.地形