【单选题】下列说法中,正确的是( )
A.
频率分布直方图中各小长方形的面积不等于相应各组的频率
C.
数据2,3,4,5的方差是数据4,6,8,10的方差的一半
【简答题】A.He enjoys writing home every week. B.He never fails to write home once a week now. C.He doesn't write home once a week now. D.He has been asked to write home every week.
【单选题】He plays basketball every day. And now he is playing piano at home. [ ]
【单选题】He takes his ______ home to his wife every Friday.
【判断题】刀尖在刀刃的最高位置时,刃倾角为正.____ 四名词解释:
【单选题】He lives far from his school. So every day He _______. [ ]
【简答题】He said that he goes home to see his parents every______week. A.another B.the second C.two D.other
【单选题】共模抑制比 K CMR 是 ( )
C.
差模放大倍数与共模放大倍数 ( 绝对值 ) 之比
D.
交流放大倍数与直流放大倍数 ( 绝对值 ) 之比