【尖上的中国】伴随着《舌尖上的中国》这部国产美食纪录片的热播...

2013年9月23日中国人民银行发行面额为5元硬币，该币正面主景图案为中华人民共和国国徽，内缘上方刊“中华人民共和国”国名、下方刊面额“伍圆”及年号“2013”；背面主景图案为“和”字的行书书法，内缘右上方刊“和”字的五种书法体．甲同学说该币是铜铸的，乙同学说可以用酒精灯灼烧下看是否变黑，就这一过程而言，属于科学研究环节中（　　）A. 设计实验B. 收集证据C. 建立假设D. 作出结论 化学

    China 's third manned spacecraft lifted off at 9:10 p.m. on Thursday to accomplish its most ambitious and risky task: spacewalk. Shenzhou VII carrying astronauts Zhai Zhigang Liu Boming and Jing Haipeng was launched from the Jiuquan Satellite Launch Center in Gansu Province into a clear sky. As is the case with such tasks in China the first few moments were tense. But then the ground control heard the voices of the astronauts. They felt physically sound they said to the joy of the scientists on the ground. The astronauts will orbit the Earth for three days 68 hours to be precise and one of them will walk in space about 343 km above the Earth on Saturday. That will be China 's first spacewalk and will make China the third country to conduct extra-vehicular activity (EVA) in space. The other two to have achieved that are the former Soviet Union and the US . The timing of the spacewalk could however be changed depending on how long it would take for the astronauts to adjust to all the factors. EVAs are necessary for China 's long-term goal of building a space station by 2020 and possibly launching a manned task to the Moon. The astronauts will land in central part of the Inner Mongolia autonomous region in a re-entry module on September 28th (Sunday). The astronauts entered the spacecraft at 6:28 p.m. Thursday checked the communication system with the ground control after reviewing the operation manual of the spaceship. The spaceship will change its orbit around 4 a.m. today. And the astronauts will start testing and putting on the EVA spacesuits which could take up to 15 hours. China launched its first manned spaceship (Shenzhou V) in October 2003 and followed it up by sending Shenzhou VI two years later. But the Shenzhou VII astronauts have a greater task in hand.   56. What can we learn from the passage ? A. This will be the third time for Chinese astronauts to have a space walk. B. Three astronauts will walk in space on schedule to conduct EVA in space. C. The Shenzhou-7 re-entry module will land on Saturday afternoon in central part of the Inner Mongolia Autonomous Region. D. The success of the spacewalk will be one step further towards China 's longer-term goal to have a space station by 2020. 57. The underlined words “such tasks in China ” in the third paragraph most probably refer to          . A. the first human spacewalk by the former Soviet Union astronaut Alexei Leonov in 1965 B. American astronaut Neil Armstrong setting foot on the Moon in 1969 C. the first two manned spaceflights of China in 2003 and 2005 D. China 's launching a manned spacecraft to the Moon 58. The main purpose of the passage is to           . A. tell a story      B. provide evidence     C. give a report   D. compare opinions    

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