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问题 选择题

某同学在进行“加酶洗衣粉和普通洗衣粉的洗涤效果”的探究实验中，设计了如下方案：①设置两组实验，分别使用蛋白酶洗衣粉和复合酶洗衣粉；②两组实验的洗衣粉用量、被洗涤的衣物质地、衣物量、污染物的性质和量、被污染的时间、洗涤时间、洗涤方式等全部设置为相同；③根据污渍去除程度得出结果。对这个实验的评价，正确的是[ ]

A．对照实验设置不合理

B．无关变量设置太多

C．没有自变量

D．因变量不能描述

答案

答案：A

阅读理解

“Cool” is a word with many meanings. It means a little cold at first. As time changes, the word gets many different meanings. We can use “cool” when we talk about something wonderful or somebody looking smart. For example. When you see a beautiful and expensive car in the street, you can say, “It is cool.” You may think the popular singer Jay Chow is cool. You can also use the word to mean something new and surprising. Here is an example. One day a teacher took the students to a farm and then asked them to write something about the visit. One of her students just wrote, “The farm is so cool.” Because he thought “cool” was the best word to show what he saw and felt. It also shows some people don’t have enough words. Without “cool”, they seem to have no other words to use. Can you think of any other words like “cool: with so many meanings? If you can they are also very “cool”.

小题1:The meaning of the word “cool” ______.

A．is always the same

B．changes a lot

C．is “wonderful or smart”

D．is “new and surprising”小题2:“You may think the popular singer Jay Chow is cool”. Here “cool” means

A．a little cold

B．a little hot

C．new and surprising

D．good-looking小题3:When some people use “cool” everywhere they don’t have other words, the writer seems a little ______.

A．excited

B．happy

C．surprised

D．worried小题4:The best title is _____.

A．Meanings of the word “Cool”

B．“Cool”, the Best Word to Use

C．People use “Cool” Too Much

D．“Cool’ Is A New Word
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选择题

下列物质在酒精灯加热时不发生分解的是

A．NaHCO3

B．KMnO4

C．HNO3

D．Na2CO3
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