【简答题】A.He was housed by Emma Thompson five years ago. B.He has graduated from an England university. C.He has become a British citizen. D.He will be 15 years old in April.
【单选题】下面的选项不属于关系数据库的性质的是( )
【判断题】因为极限偏差有正负,所以尺寸公差值可以是0或正值。
【单选题】(Even though) Sedat (has been studying) English for three years before he came (to the United States), It is still difficult for him (to express himself).
【单选题】以下数据库系统中不属于关系型数据库的是 。
【简答题】电路如图所示。已知 RL= 5Ω,试求电路中的电流 I 。