2013年9月9日,WTA官网公布最新一期网球女单选手世界排名,我国女选手李娜位

题型:多选题

问题:

2013年9月9日,WTA官网公布最新一期网球女单选手世界排名,我国女选手李娜位居第5位,如图所示,李娜在边界A处正上方B点将球水平向右击出,球恰好过网C落在D处,已知AB高h1=1.8m,x=18.3m,CD=9.15m,网高为h2,不计空气阻力,则(  )

A.球网上边缘的高度h2=1m

B.若保持击球位置、高度和击球方向不变,球刚被击出时的速率为60m/s,球一定能落在对方界内

C.任意增加击球高度,只要击球初速度合适,球一定能落在对方界内

D.任意降低击球高度(仍高于h2),只要击球初速度合适,球一定能落在对方界内

考点:平抛运动
题型:多选题

在列车编组站里,一辆m1=2×104kg的货车在平直轨道上以v1=1.8m/s的速度运动,碰上一辆m2=2.2×104kg的静止的货车,它们碰撞后接合在一起继续运动,求运动的速度。

题型:多选题

老年多发性腹股沟斜疝,最好的手术方法是()

A.单纯疝囊高位结扎术

B.巴西尼(Bassini)法

C.佛格逊(Ferguson)法

D.麦克凡(McVay)法

E.内环修补法

题型:多选题
    短文改错  
    此题要求改正所给短文中的错误,对标有题号的每一行作出判断:
    如有错误(每行只有一个错误),则改正.
Dear Mr David Harris,
    I'm very happy to write to you because I accepted the admission notice                               1. _____ 
in Beijing University yesterday. I'll study IT,                                                                            2.        _ 
that I have been dreaming about.                                                                                            3.         _ 
    Mr Harris, I still remember on the first day when you taught us three years ago.                   4.        _ 
We were quite shy and poorly at listening and                                                                         5.        _ 
speaking. You encourage us to practise as much as possible. Your teaching was so                 6.         _
interesting that all of us attracted.                                                                                            7.         _
With your helps I improved my English, and in NMF,T I got                                                   8.           
the satisfactory result. Mr Harris, thank you very much indeed. How are you now                   9.           
in Chicago? Hope to hear you soon.                                                                                       10.        _
                                                                                             Yours.
                                                                                                 Li Wei
题型:多选题

穿脱隔离衣的操作步骤正确的是( )。

A.双手伸入袖内后扣袖扣
B.扣好领扣后系腰带
C.将腰带交叉在背后打结
D.消毒手后先解开领扣
E.将隔离衣内面向外,挂传染病室内

题型:多选题

()是一种断裂破坏型的一次性使用的安全泄压装置,用来装设在那些不适宜装设安全阀的压力容器上,当容器内的压力超过(设定压力)值时,自行爆破,使容器内的气体经爆破片断裂后形成的流出口向外排出,避免容器本体发生爆炸。

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