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【简答题】
已知某种灯泡寿命服从正态分布，在某星期所生产的该种灯泡中随机抽取10只，测得其寿命(单位：h)为 1067，919，1196，785，1126，936，918，1156，920，948 设总体参数都未知，试用最大似然法估计这个星期中生产的灯泡能使用1300小时以上的概率．
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【简答题】在旧社会,我们评剧演员常常挣钱不够吃饭,艺人们大都是拉家带口,生活困难。A. In
the old society, pingju performers
seldom made enough to live on, and as most were saddled with big families,
their life was hard. B. In the old society, ping...
【简答题】有四种元素A、B、C、D位于元素周期表的前四周期，已知它们的核电荷数依次增大，且核电荷数之和为50；A为构成化合物种类最多的一种元素；B原子的L层p轨道中有2个电子；C与B原子的价层电子数相同；D原子的K层电子数与最外层电子数之比为2∶1. 请回答下列问题。 (1)写出D 2+ 价层电子排布图__________________，其最外层有_________个单电子； (2) B的最高价氧化物和C...
【简答题】1 如图所示,根据提示的绘制过程,完成填空。绘制过程:利用()命令绘制边长为50的正方形,利用()命令,旋转()度,完成立起来的正方形1。再利用()命令绘制正方形对角线,完成2,利用圆命令中的()绘圆方式,完成右下角小圆3,同理绘制出其他三个小圆。再利用圆命令中的()绘圆方式,捕捉小圆的(),完成大圆4。最后用()命令,完成位置5的处理。
【单选题】如下图所示的正方形,边长为 50 ,其 a 点为 (10,10) ,则 b 点的坐标正确的是:
A.
相对于 a 点 (@50<30)< /div>
B.
相对于 a 点 (@53.5013,35.0000)
C.
相对于坐标原点 (50.000,25.0000)
D.
相对于坐标原点 (50<30)< /div>
【单选题】在旧社会里，我们评剧演员常常挣钱不够吃饭，艺人们大都是拉家带口，生活困难。
A.
In the old society, Pingju performers seldom made enough to live on, and as most were saddled with big families, their life was hard.
B.
In the old society, Pingju performers couldn't earn enough money to live on. Most of them were saddled with big families, their life was hard.
C.
In the old society, Pingju performers seldom made enough money to eat. Most of them were saddled with big families, and their life was hard.
D.
In the old society, Pingju performers couldn't earn enough money to eat. Most of them were saddled with big families, and their life was hard.
【单选题】李丽中专毕业后就职于一家服饰公司,她定下“两年内当上班组主管。从此,李丽工作踏实认真,虚心好学,刻苦勤勉虽然工作辛苦但她体会到生活的充实,也掌握了先进的生产技术。不到一年,李丽就走上了班组主管的岗位。这说明( )
A.
人生目标一但确定就能实现
B.
确定人生目标要符合自身实际
C.
平凡的工作岗位上不需要人生目标
D.
人生目标应追求“高大上”
【单选题】在旧社会,我们评剧演员常常挣钱不够吃饭,艺人们大都是拉家带口,生活困难。
A.
In the old society, pingju performers seldom made enough to live on, and as most were saddled with big families, their life was hard.
B.
In the old society, pingju performers couldn't earn enough money to live on. Most of them were saddled with big families, their life was hard.
C.
In the old society, pingju performers seldom made enough money to eat. Most of them were saddled with big families, and their life was hard
D.
In the old society, pingju performers couldn't earn enough money to eat, as most were saddled with big families, their life was hard.
相关题目：
【单选题】如下图所示的正方形,边长为 50 ,其 a 点为 (10,10) ,则 b 点的坐标正确的是:
A.
相对于 a 点 (@50<30)< /div>
B.
相对于 a 点 (@53.5013,35.0000)
C.
相对于坐标原点 (50.000,25.0000)
D.
相对于坐标原点 (50<30)< /div>