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用40m/s的初速度水平抛出一个物体，经过一段时间后，物体速度方向与水平成37°角，求：此时物体相对于抛出点的水平位移和竖直位移．（g=10m/s2，sin37°=0.6，cos37°=0.8，tan37°=0.75）

答案

根据平行四边形定则得，vy=v0tan37°=40×

3
4
m/s=30m/s．

则运动的时间t=

vy
g
=
30
10
s=3s．

则x=v0t=40×3m=120m．

竖直位移y=

1
2
gt2=
1
2
×10×9m=45m．

答：物体相对于抛出点的水平位移为120m，竖直位移为45m．

战国时期发生的著名战役有（　　）

①牧野大战　　②城濮大战　　③围魏救赵　　④长平之战

A．①②

B．②③

C．②④

D．③④
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听力题

A) 根据短文内容和所给汉语提示，写出空白处各单词的正确形式。（每空一词）

It’s no surprise that Laura Fagan is smiling—she has the sweetest job in the   1  (世界). Her job is to taste chocolate, desserts and cakes.

Laura works in the    2  (有名的)supermarket, Tesco. Her job is to try different kinds of desserts. She needs to try to travel to different    3  (城市)to try different desserts.

Although the job seems to be great, it is hard. Usually, Laura begins trying desserts as   4  (早地) as 8 am, and still trying new desserts at 6 pm    5   (在…之前)she goes back home. Fortunately, the job hasn’t made her too fat. She   6   (仅仅，只) worries about her teeth.

“Of course I was afraid of becoming fat when I   7  (开始) the job, so I try to do   8  (更多的) exercise. The main    9  (事情) is my teeth. I don’t think my dentist would be happy if I told them what I do, so I try to brush my teeth as often as    10  (可能的).”
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