【简答题】Your duty now is______ (study).
【单选题】双击窗口标题栏空白位置,窗口会在( )显示之间转换
【简答题】线性方程组有解当且仅当它的系数矩阵的秩与增广矩阵的秩 .
【简答题】Is your son showing his friends the photos now? (用often代替now) _______________________________________________________?
【判断题】若两个电容器并联后使用,电容器组的耐压值是其中耐压值最小的耐压值。
【单选题】I used to _____ a lot, but now I have become fatter, for I mainly stay at home watching TV. [ ]
【单选题】I turned over the chinese vase by accident while I cleaned the desk and now it is _________.
【判断题】设 是非零矩阵,则 的秩为 当且仅当 的行向量组的秩为 。
【单选题】We have been on duty for four hours and ____. [ ]
B.
now does your tum come