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（B组）发射神舟五号飞船的火箭（连同上端的飞船）总高度为58m，发射塔高度为70m．一人在观看电视直播报道时，在头脑中记下火箭上端的位置A（如图），用自己的手表测出火箭从开始发射到下端通过A点用的时间约为8s．假设火箭开始阶段是匀加速直线运动，请你根据上述已知条件，求出火箭在开始运动阶段的两个运动学物理量．

答案

根据匀加速运动的位移公式s=

1
2
at2

得a=

2s
t2
=
2×58
82
m/s2=1.81m/s2

根据匀变速运动的平均速度公式

.
v
=
v0+v
2
=
0+v
2

得v=2

.
v
=2×
58
8
m/s=14.5m/s

答：可以求出火箭的加速度a=1.81m/s2，

以及火箭的末端通过A处的速度v=14.5m/s．

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下颌智齿冠周炎可引起 （）

A.眶下间隙感染

B.面颊瘘

C.翼下颌间隙感染

D.下颌骨边缘性骨髓炎

E.下颌下间隙感染
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填空题

短文填词。

     阅读下面短文，根据以下提示：1）汉语提示，2）首字母提示，3）语境提示，在每个空格内填

入一个适当的英语单词，并将该词完整地写在右边相对应的横线上。所填单词要求意义准确，拼写

正确。

     During the Spring Festival, my parents and some of my relatives gave me some gift money. What should I

do (1) ____ the money? I had desired to buy a pair of Nike sports (2) ____(鞋). I had also wanted to have an

MP4 player of my (3) ____. With the gift money I could a (4) ____ what I wanted to buy. However, I soon

gave up the idea (5) b____I knew I was still a student at school. Besides, my parents always lived a (6) s____

life. Their money was not (7)____(容易) earned. Thinking of this, I decided to open a savings account at a

bank the (8) f ____ day. From now on, I'll make both ends meet as a student financially (9) ____ (支持) by

my parents. I am sure my dream will (10) ____ true one day with the money through my hard work.

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