题干

人参是一种名贵药材,具有良好的滋补作用。口服α-干扰素在慢性乙肝、丙肝及部分肿瘤的治疗中有一定疗效。下图为科研人员制备能合成干扰素的人参愈伤组织细胞的流程,①~④表示相关的操作,EcoRⅠ、BamHⅠ为限制酶,它们的识别序列及切割位点如表所示。请回答下列问题:

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    If you are given only 1 yuan, can you live in a city for one day? It may be a little difficult. But 1 from Xi'an did it.

    On April 10th, more than 60 students from the Middle School Attached to Northwestern Polytechnical University 2 the One Yuan Metropolis Survival. The charity for teenagers called Imperceptible Education held this 3  .  Students had to live and they had to deal with a lot of  4  tasks. It has happened in eight cities and is going to four others, including Beijing, in May.  

    To  5  , many students looked for part-time jobs and saw how hard life was. Zhang Qiyue, 14, asked more than 10 restaurants for a job and 6   got one chance. "We were sad when they said   7  . But slowly, we got used to it," he said. After being a waiter for an hour, he 8   25 yuan.

    Some made use of their talents  9  singing and dancing in parks or shopping malls. Many people who walked by took notice and helped   10  . Zhao Jiacheng, 14, drew pictures and made paper crafts (手工). "This showed it's  11 to learn a special skill," he said.

    Living was hard,    12 finishing the tasks was not any easier. They went to different places to finish tasks in a  13  time. The most amazing one was when they had to exchange things worth a hundred yuan with only a piece of paper in half an hour. "We learned  14   to persuade (说服) others. From a balloon to a cake to a bottle of yogurt……, after almost 20 tries, we got an expensive necklace, "he said, "we would   15 all of the money we had raised to poor schools in Tibet."