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阅读理解 Three kids have been learning chemistry for only a few months. But they have already begun to challenge a world famous scientist! Li Weichi, Huang Runling, and Xiao Yan are from Zhongshan Huaqiao Middle School in Guangdong. They have just found a red cabbage that could be a new kind of acid-base indicator (酸碱指示剂). They want it to take the place of litmus (石蕊) paper. 'We've learnt to think of and ask questions about life by ourselves,' said Li, 'We work well with each other.' British scientist Robert Boyle discovered the use of litmus paper over 300 years ago. Now it is used widely in experiments all over the world. But when the kids did some experiments in class last winter, they saw that the litmus paper didn't turn very blue with base matter. It's hard to get a clear result. Will there be a better indicator than litmus paper? The three kids decided to try and find out! How? They went to collect over 40 plants in parks, gardens and markets. Then they ground (研磨) leaves, flowers and stems (茎) to get the pigments (色素) from them. The kids mixed pigments with acid and base. They spent months watching carefully to see which paper showed the best colour change. They decided it was the litmus paper! 'It's our first scientific journey, Huang said, 'But it makes me want to try harder.' 1. Whom did the three kids want to challenge? A. Their chemistry teacher. B. Their headmaster. C. Robert Boyle D. Thomas Edison 2. From the text, a red cabbage is a kind of ____. A. plant B. animal C. paper D. liquid 3. What's the right order for the following sentences? a. Three kids collect red cabbage everywhere. b. The kids mixed pigments with acid and base. c. The kid ground the red cabbage. d. The kids get pigments from it. A. a-b-c-d B. b-a-c-d C. a-c-d-b D. b-c-d-a 4. What is widely used as the acid-base indicator now? A. red cabbage B. litmus paper C. any plant D. any flower 5. The story mainly tells us ____. A. how to make litmus paper B. about the three kids' spirit C. scientist were wrong D. the kids are heroes
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【判断题】具有面心立方晶体结构的金属材料塑性较好
A.
正确
B.
错误
【判断题】具有面心立方结构的金属材料塑性较好。
A.
正确
B.
错误
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【简答题】请编写一个程序,查询MyData数据库中student表中的所有的数据(id,name,age)并输出在控制台
【单选题】对 于 植 物 神经,可 兴奋 迷走 神经的频 率 是
A.
0 ~ 5 Hz
B.
5~10 Hz
C.
10 ~ 50 Hz
D.
50~100 Hz
【判断题】对于植物神经,可兴奋迷走神经的频率是50~100Hz
A.
正确
B.
错误
【单选题】对于植物神经,可兴奋迷走神经的频率是()
A.
0~5Hz
B.
5~10Hz
C.
10~50Hz
D.
50~100Hz
E.
100~150Hz
【单选题】采用连续观测定位法,可以测定_____。I、风压差;Ⅱ、流压差;Ⅲ、风流压差
A.
IⅡ
B.
IⅢ
C.
ⅡⅢ
D.
IⅡⅢ
【多选题】现实中,()等类型的内容题材上能较为集中而显著地反映出一个媒介的品位。
A.
有关死亡
B.
有关性
C.
有关残疾
D.
有关战争
【简答题】请编写一个程序,查询MyData数据库中员工表(emplory)表中的所有的数据(id,name,gender,salary)并输出在控制台。
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