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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】[判断题] 毕业生凭学校发放的就业协议书,在与用人单位签约后交学校就业工作部门签章。此程序由学校作最后把关,有利于维护学生的合法权益。()
A.
正确
B.
错误
【单选题】维生素B1最主要的营养作用是
A.
调节机体物质代谢和能量代谢
B.
促进生长发育
C.
影响DNA的合成
D.
有利于胃肠道正常蠕动
E.
影响内分泌系统
【简答题】去除植物病毒的主要方法是组培法和()两种方法,当把二者结合起来脱毒效果最好。
【简答题】人工湿地系统设计的主要工艺参数是什么?应考虑哪些问题?
【单选题】维生素B1最主要的营养作用是
A.
.调节机体物质代谢和能量代谢
B.
.促进生长发育
C.
.影响NA的合成
D.
.有利于胃肠道正常蠕动
E.
.影响内分泌系统
【多选题】下面那些算法的时间复杂度为O(n 2 )
A.
顺序查找
B.
折半查找
C.
插入排序
D.
冒泡排序
E.
折半插入排序
【单选题】读七大洲轮廓图,其中亚洲是
A.
B.
C.
D.
E.
F.
G.
G
【简答题】去除植物病毒的主要方法是___和___两种方法,当把二者结合起来脱毒效果最好。
【单选题】维生素B1最主要的营养作用是
A.
促进生长发育
B.
调节消化液分泌
C.
影响内分泌功能
D.
影响DNA合成
E.
调节机体物质代谢和能量代谢
【单选题】维生素 B 1 最主要的营养作用是
A.
调节机体物质代谢和能量代谢
B.
有利于胃肠道正常蠕动
C.
促进生长发育
D.
影响内分泌系统
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