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【单选题】
关于随机抽样研究中，下列描述哪项是不正确的
A.
实行抽样时，要使总体中每个个体都有同等机会被抽到
B.
采集样本应遵循随机化原则
C.
调查者可在总体中，随意抽取总体中任意部分，作为样本
D.
抽取的样本对总体要有代表性
E.
严格控制的随机抽样有助减少样本的偏性
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【单选题】某儿童认为周围世界绕着他转，月亮跟着他走；他只知道自己有个哥哥，但不知道自己就是哥哥的弟弟。该儿童心理发展所处的阶段是（ ）
A.
具体运算阶段
B.
后运算阶段
C.
前运算阶段
D.
形式运算阶段
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【单选题】两个同频率正弦交流电压 u 1 、 u 2 的有 效值各为20V和30V。当 u 1 + u 2 的有效值为-10V时, u 1 与 u 2 的相位 差是 ( )
A.
0 o
B.
180 o
C.
90 o
D.
270 o
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【单选题】Saving Money Where you save your money often depends on what you are saving for. If you are saving to buy a dictionary or to go to a concert, then probably keep your money somewhere in your room. If y...
B.
Putting your money in a piggy bank,
C.
Putting your money in your pocket.
D.
Putting your money in a savings account.
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【单选题】SECTION B PASSAGES Directions: In this section, you will hear several passages. Listen to the passages carefully and then answer the questions that follow. 听力原文： A few months ago, millions of people i...
A.
One of the bridges between North and South London collapsed.
B.
The heart of London was flooded.
C.
An emergency exercise was conducted.
D.
100 people in the suburbs were drowned.
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【单选题】要对演示文稿中所有幻灯片做同样的操作,一下选项正确的是______.
A.
使用制作副本
B.
使用母版
C.
使用幻灯片放映
D.
使用超级链接
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【单选题】两个同频率正弦交流电压u 1 、u 2 的有效值各为60 V和80 V。当u=u 1 +u 2 的有效值为140 V时,u 1 和u 2 的相位差是( )
A.
0°
B.
180°
C.
90°
D.
45°
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【单选题】以下关于好的面向对象程序设计语言的叙述中,不正确的是 。
A.
应该支持被封装的对象
B.
应该支持类与实例的概念
C.
应该支持通过指针进行引用
D.
应该支持继承和多态
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【简答题】Time spent in a bookshop can be enjoyable. If you go to a ___36___shop, no assistant will come near to you and say “Can I help you? ” You ____37____buy anything you don’t want. You may try to ___38___...
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【单选题】两个同频率正弦交流电压 u 1 、 u 2 的有 效值各为30V和50V。当 u 1 + u 2 的有效值为80V时, u 1 与 u 2 的相位 差是 ( )
A.
0 o
B.
180 o
C.
90 o
D.
270 o
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【单选题】SECTION B PASSAGES Directions: In this section, you will hear several passages. Listen to the passages carefully and then answer the questions that follow. 听力原文： (11) A few months ago, millions of peo...
A.
One of the bridges between North and South London collapsed
B.
The heart of London was flooded.
C.
An emergency exercise was conducted.
D.
100 people in the suburbs were drowned.
查看完整题目与答案
相关题目：
【单选题】某儿童认为周围世界绕着他转，月亮跟着他走；他只知道自己有个哥哥，但不知道自己就是哥哥的弟弟。该儿童心理发展所处的阶段是（ ）
A.
具体运算阶段
B.
后运算阶段
C.
前运算阶段
D.
形式运算阶段
查看完整题目与答案
【单选题】两个同频率正弦交流电压 u 1 、 u 2 的有 效值各为20V和30V。当 u 1 + u 2 的有效值为-10V时, u 1 与 u 2 的相位 差是 ( )
A.
0 o
B.
180 o
C.
90 o
D.
270 o
查看完整题目与答案
【单选题】Saving Money Where you save your money often depends on what you are saving for. If you are saving to buy a dictionary or to go to a concert, then probably keep your money somewhere in your room. If y...
B.
Putting your money in a piggy bank,
C.
Putting your money in your pocket.
D.
Putting your money in a savings account.
查看完整题目与答案
【单选题】SECTION B PASSAGES Directions: In this section, you will hear several passages. Listen to the passages carefully and then answer the questions that follow. 听力原文： A few months ago, millions of people i...
A.
One of the bridges between North and South London collapsed.
B.
The heart of London was flooded.
C.
An emergency exercise was conducted.
D.
100 people in the suburbs were drowned.
查看完整题目与答案
【单选题】要对演示文稿中所有幻灯片做同样的操作,一下选项正确的是______.
A.
使用制作副本
B.
使用母版
C.
使用幻灯片放映
D.
使用超级链接
查看完整题目与答案
【单选题】两个同频率正弦交流电压u 1 、u 2 的有效值各为60 V和80 V。当u=u 1 +u 2 的有效值为140 V时,u 1 和u 2 的相位差是( )
A.
0°
B.
180°
C.
90°
D.
45°
查看完整题目与答案
【单选题】以下关于好的面向对象程序设计语言的叙述中,不正确的是 。
A.
应该支持被封装的对象
B.
应该支持类与实例的概念
C.
应该支持通过指针进行引用
D.
应该支持继承和多态
查看完整题目与答案
【简答题】Time spent in a bookshop can be enjoyable. If you go to a ___36___shop, no assistant will come near to you and say “Can I help you? ” You ____37____buy anything you don’t want. You may try to ___38___...
查看完整题目与答案
【单选题】两个同频率正弦交流电压 u 1 、 u 2 的有 效值各为30V和50V。当 u 1 + u 2 的有效值为80V时, u 1 与 u 2 的相位 差是 ( )
A.
0 o
B.
180 o
C.
90 o
D.
270 o
查看完整题目与答案
【单选题】SECTION B PASSAGES Directions: In this section, you will hear several passages. Listen to the passages carefully and then answer the questions that follow. 听力原文： (11) A few months ago, millions of peo...
A.
One of the bridges between North and South London collapsed
B.
The heart of London was flooded.
C.
An emergency exercise was conducted.
D.
100 people in the suburbs were drowned.
查看完整题目与答案
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