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【判断题】
控制无关变量是教育研究设计中最重要的、也是最复杂的内容。为了避免研究过程中变量的相互混淆,必须对无关变量进行控制。控制的基本原则是尽可能减少无关变量对自变量和因变量的干扰A.
正确
B.
错误
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【单选题】Absolute poverty has fallen steadily since the industrial revolution, which is why yesterday's ______ have become today's necessities.
A.
refreshments
B.
accommodations
C.
entertainments
D.
luxuries
【简答题】I hear that little beggar of mine let fly _____- you with his catapult yesterd
【简答题】听音，补全句子。 1. What did he do _________________________? 2. My mother _________________________ yesterday. 3. Liu Tao _________________________ two days ago. 4. Helen has a _________________________. 5. ...
【简答题】比较下列各组化合物的熔点的大小,并做简要解释。 ( 1 ) 和 KCl ;( 2 ) NaCl 和 NaBr 。
【单选题】The proposal that Tom ______ was unanimously approved at the regular board meeting yesterday.
A.
be dismissed
B.
dismissed
C.
was dismissing
D.
was dismissed
【单选题】Which of the following is Not mentioned in the passage?
A.
The sandstorm which ended yesterday morning.
B.
An earlier storm last weekend.
C.
Some sandstorms in the Inner Mongolia.
D.
The sandstorm happening last year.
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