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【简答题】
Jack London was a famous American writer. He was born on January 12, 1876, in America. His family was very poor, and Jack had to leave school to make a living when he was twelve. He worked very hard. Later Jack returned to school. He was strict with himself and worked hard at every subject, especially ( 尤其 ) literature ( 文学 ) . Can you imagine a world without the Internet? It ’ s surprising to think about it. Now, China has more than 162 million Internet users, according to the China Internet Network Information Centre. This is the second highest number of user in the world after the United States. Today, 66% of Chinese “ netizens (网民) ” are teenagers. “ They spend about thirteen hours every week online, ” said Qian Hulin, an Internet expert (专家)。 Doctor Song in Beijing Xuanwu Hospital said about 14% of Chinese netizens who are teens often lasted over ten hours to play online games. The main reasons why teenagers surf the Web are to search for information, to communicate with others and to have fun. On the Internet, teenagers can find out almost anything. And surfing the Web can help students with their homework and widen their knowledg e. Li Dong, a teacher at No. 41 Middle School in Shijiazhuang, likes her students to use the Internet. “ When we talk in class, students who surf the Net usually know more background information than the others, ” she said. In addition, people can use the Internet to write letters or stories and send emails. Many teens keep in touch with their friends online. It is cheaper than phoning somebody far away and also much quicker.
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【单选题】比赛中,队员不得在()之内借助同伴或任何物体支持进行击球。
A.
比赛场地
B.
比赛场区
C.
无障碍区
【判断题】1M 乙酸铵交换法测定土壤CEC制备铵饱和土壤时,洗涤溶液可以收集起来用于测定交换性盐基的含量。
A.
正确
B.
错误
【简答题】元曲分为( )和( )两种。
【单选题】用乙酸钠法测定石灰性土壤和盐碱土CEC,下列说法错误的是
A.
醋酸钠作为交换剂的优点在于:对碳酸钙的溶解度小
B.
醋酸钠作为交换剂的优点在于:对于2:1型粘土矿物,片层内的阳离子也可以被Na取代,而保持在内层的Na又能被NH4置换出来,而如果用醋酸铵作为交换剂,虽然铵离子能将片层内的阳离子置换下来,但是进入片层的铵活性会降低,导致CEC的测定结果偏低。
C.
先用1M乙酸钠溶液制备Na+饱和土壤,再用1M 乙酸铵溶液处理Na+饱和土壤,并利用NH4+交换出土壤中的交换性Na+
D.
用火焰光度计测定溶液中NH+浓度
【单选题】涂片一般适用于
A.
骨组织
B.
肌组织
C.
神经组织
D.
血液
【多选题】涂片一般适用于
A.
肌组织
B.
骨组织
C.
骨髓
D.
血液
【判断题】队员不得在比赛场地之内借助同伴或任何物体支持进行击球,但是队员可以挡住或拉住另一名即将犯规的同队队员。
A.
正确
B.
错误
【简答题】元曲分为()和()。
【单选题】涂片一般适用于
A.
上皮组织
B.
血液
C.
骨组织
D.
肌组织
【单选题】涂片一般适用于
A.
上皮组织
B.
骨组织
C.
肌组织
D.
神经组织
E.
血液
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