一质量m=2kg的物块放于水平面．在与水平面成α=37°斜向上的拉力F=10N作用下，从静止开始向右运动s=5m的距离，物块与水平面间的动摩擦因数μ=0.2，g=10m/s²，sin37°=0.6，cos37°=0.8  求：

西北地区的气候特点是（　　）

    Humans like to live and work in groups. Language is the “cement(胶合剂)”____holds these groups together. Language is part of culture. Culture, in this sense,____ (mean) all those customs, skills, and attitudes that are part of the behavior of a ____ (particularly) group. What you think ____ what you want in life are all affected by the culture of the group in which you ____( raise). Groups of people live in different ways. They may have different skills, organizations, and art forms. Their family life may be completely different from yours.

    Human beings are inventive animals. They can decide to change their cultures in order to meet various ____(situation). Of all living things, human beings are the ____(clever). They can choose ____(live) in many environments and in a wide variety of ways. Only human beings can choose where and how they want to live and then improve the physical environment to help ____(they)realize these choices.

    Acquiring the wisdom to make wise choices ____ (be)the lasting challenge of being human.

      【甲】陈胜者，阳城人也，字涉。吴广者，阳夏人也，字叔。陈涉少时，尝与人佣耕，辍耕之垄上，怅恨久之，曰：“苟富贵，无相忘。”庸者笑而应曰：“若为佣耕，何富贵也？”陈涉太息曰：“嗟乎，燕雀安知鸿鹄之志哉！”……行收兵。比至陈，车六七百乘，骑千余，卒数万人。攻陈，陈守令皆不在，独守丞与战谯门中。弗胜，守丞死，乃入据陈。数日，号令召三老、豪杰与皆来会计事。三老、豪杰皆曰：“将军身被坚执锐，伐无道，诛暴秦，复立楚国之社稷，功宜为王。”陈涉乃立为王，号为张楚。当此时，诸郡县苦秦吏者，皆刑其长吏，杀之以应陈涉。

      【乙】陈胜王凡六月。已为王，王陈。其故人尝与庸耕者闻之，之陈，扣宫门曰：“吾欲见涉。”宫门令欲缚之。自辩数，乃置，不肯为通。陈王出，遮道而呼涉。陈王闻之，乃召见，载与俱归。入宫，见殿屋帷帐，客曰：“夥颐！涉之为王沈沈者！”楚人谓多为夥，故天下传之，夥涉为王，由陈涉始。客出入愈益发舒，言陈王故情。或说陈王曰：“客愚无知，颛妄言，轻威。”陈王斩之。诸陈王故人皆自引去，由是无亲陈王者。