【单选题】某晶体管的发射极电流是1mA, 基极电流是20uA, 则它的集电极电流是
【简答题】在某放大电路中,测得晶体管的三个电极1、2、3的流入电流分别为-1.22mA、0.02mA、1.2mA。 由此可判断电极1是____,电极2是____,电极3是____(A、发射极, B、基极, C、集电极); 该晶体管的类型是____(A、PNP型 ,B、NPN型); 该晶体管的共射电流放大系数约为____( A、40 , B、60 , C、100)。
【单选题】----The boss said we had only three days to finish the task. ----No problem. We have already _________ two thirds of it.
【单选题】一选择题有四个选项,由经验数据可知学生知道答案的概率是0.8。现随机抽取一名学生的试卷,发现该题回答正确,则此学生确实知道正确答案的概率是________。
【单选题】We had three sets of garden tools and we seemed to have no use for ______. [ ]
【简答题】一选择题有四个选项,由经验数据可知学生知道答案的概率是0.8. 现随机抽取一名学生的试卷,发现该题回答正确,求此学生确实知道正确答案的概率
【简答题】一选择题有四个选项,由经验数据可知学生知道答案的概率是0.8。现随机抽取一名学生的试卷,发现该题回答正确,则此学生确实知道正确答案的概率是________。(保留三位有效数字)
【单选题】It's the first time that we ______ a quarrel.
【单选题】We (had lived) in this house for three years (while) my father decided (to have) us (move) to a new neighborhood.
【单选题】The country needs a ______ government. We have had three prime ministers in a year.