在生物课上，老师告诉同学们：“微生物很小，枝原体直径只有0.1微米”，这相当于________________米(1米=106微米，请用科学记数法表示).
1×10-7
绝对值小于1的正数也可以利用科学记数法表示，一般形式为a×10-n，与较大数的科学记数法不同的是其所使用的是负指数幂，指数由原数左边起第一个不为零的数字前面的0的个数所决定．0.1微米=1×10-7米．
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| Most adults once studied at school, had classes and did their homework every day. The same 1 is going on at school now. 2 it seems that doing weekend homework is another problem for the 3 students. All the students 4 that weekend homework should be abolished (取消). It is 5 for them to study at school five days a week. They have a lot of interests. 6 homework to do on Saturday and Sunday, when can they 7 time to help their parents do the housework, go and see a football or basketball game or a good 8 , join in family recreation (娱乐), or just have a rest at home? Because of these other activities, the homework can't be finished 9 Sunday evening. So their weekend homework is usually done in such a hurry that on Monday teachers are 10 and often threaten (威胁) to 11 the whole class of students because many of the students know 12 about the lessons. 13 there were no weekend homework to do, they would be 14 to go to school on Monday after 15 good rest and to learn what the teachers teach. | ||||
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