．瑞士中学教师巴尔末成功地从光谱数据，…中，发现规律得到巴尔末公式，从而打开了光谱奥妙的大门，请按这种规律写出第7个数据是_________．
______ terrible life the people in the mountains lived at that time！
Our teacher lives in a poorly decorated apartment, ______ the south.
I was about to leave my house______ the telephone rang.
A computer costs about ______ of a typewriter.
---When did you arrive here? ---Just ______when you left.
，…中，发现规律得到巴尔末公式，从而打开了光谱奥妙的大门，请按这种规律写出第7个数据是_________．
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