题干

如果正整数n使得[
n
2
]+[
n
3
]+[
n
4
]+[
n
5
]+[
n
6
]=69.则n为____ .(其中[x]表示不超过x的最大整数)
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48

同类题3

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    Being mistreated at work can out their negative emotions on loved ones at home. But a new study suggests that getting more exercise and sleep may help people better pope with them by, leaving them at work where they belong.

    Previous research shows that employees who are looked down on or insulted by colleagues are likely, go express their frustrations and behave angrily toward people outside of work, says study co-author Shannon Taylor, a management professor at the University of Central Florida's College of Business.

    The new study backs up this idea, but offers a bit of good news as well: Employees who averaged more than 10.500, steps a day or burned at least 2, 100 calories were less likely to mistreat their cohabitants than those who averaged fewer steps of burned fewer calories.

    The findings also revealed that when employees felt they had a bad night's sleep because of work issues, they, were more likely to be grouchy at home. “When you're tired, you're either less able or less motivated to regulate yourself” says co-author Larissa Barber, a professor of psychology at Northern Illinois University.

    Physical activity seems to counterbalance poor sleepy, Barber says, because it promotes healthy brain functions needed to properly regulate emotions and behaviors. “This study suggests that high amounts of exercise can be at least one way to improve the situations brought by sleep troubles that lead to negative behaviors at home,” she says.

    Barber acknowledges that finding time to work out and get a full night's sleep can be difficult when work pressure is mounting, and that often, job stress can be directly related to sleep quality. But, she says, making the effort to burn some extra calories and blow off some steam can be worth it. It's not only good for you, says Taylor,/ but it can benefit the people you live with as well.

同类题5

关注世界,关注未来,关注国家的发展。2011年是苏联解体20周年,以史为鉴,继往开来。阅读材料,结合所学知识回答下列问题。

材料一  1918—1937年苏联农业集体化运动发展状况表

项目

1918年

1929年

1930年

1934年

1937年

集体农庄数(单位:千个)

1.6

57.0

85.9

233.3

243

参加集体农庄的户数(单位:百万户)

0.02

1.0

6.0

15.7

18.5

集体化的比重:占农户总数的百分比

0.1

3.9

23.6

71.4

93.0

占总播种面积的百分比

不详

14.9

33.6

87.4

99.1

——齐世荣主编《世界通史资料选辑》现代部分第一分册,商务印书馆1980年版

材料二  (赫鲁晓夫提出)在最近十年(1961—1970年)里,苏联在建立共产主义的物质技术基础上,在按人口平均计算的产量方面将超过最强大最富裕的资本主义国家——美国。

在第二个十年(1971—1980年)结束时,……苏联将基本上建成共产主义社会。完全建成共产主义社会将在下一个时期完成。

——齐世荣主编:《当代世界史资料选辑》第一分册,北京师范学院出版社1989年版

材料三  勃列日涅夫改革分为三个阶段:第一阶段为20世纪60年代中期至70年代初,苏联工业年均增长率为8.4%。第二阶段为70年代初到70年代末,1971—1975年,工业总产值年增长率为7.1%,比前五年下降1.3%,其后五年又下降2.6%。第三阶段,从70年代末到80年代初,1982年工业总产值仅增长2.8%。

——《历史2(必修)·历史材料与解析》人教社2007年版

材料四  1981—1985年,苏联国民生产总值平均增长率为5.1%、3.1%、2.2%、1.8%。因此,戈尔巴乔夫一上任就惊呼,“国内形势已经潜伏着严重的社会经济危机。”

——《历史2(必修)·历史材料与解析》人教社2007年版