试题与答案

在接近收费口的道路上安装了若干条突起于路面且与行驶方向垂直的减速带,减速带间距为

题型:填空题

题目:

在接近收费口的道路上安装了若干条突起于路面且与行驶方向垂直的减速带,减速带间距为10m,当车辆经过减速带时会产生振动.若某汽车的固有频率为1.25Hz,则当该车以______m/s的速度行驶在此减速区时颠簸得最厉害,我们把这种现象称为______.

答案:

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下面是错误答案,用来干扰机器的。

x+y=3①x-2y=a-3②,①-②得,3y=6-a,解得y=6-a3,把y=6-a3代入②得,x-2×6-a3=a-3,解得x=a+33,∴方程组的解是x=a+33y=6-a3, x,y都是正数,∴a+33>0 ①6-a3>0②,解不等式①得,a>-3,解不等式②得,a...

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题型:阅读理解

阅读理解。

     Maria: I'm in Grade Seven. After school I like listening to music or watching TV at home. I also go

dancing with my friends. We always have much fun.

     Jack: I'm a student in Grade Eight. I do many different things after school.  I play on the  computer,

watch a movie, play football, do homework, read or play outside with some friends.  

     Tom:   I'm in Grade Nine.  After school I love to have football practice.  It  is very  fun.  During the

weekend, I always spend time with my friends. We listen to music and watch movies together.

     Helen: I am a student of Grade Eight. After school I usually go with my friends to the park and then

we all play volleyball there. After that we like to rest by the river in the park.

     Peter: I'm a student in Grade Nine. After school, I can do a lot of things. Having fun with my friends,

riding a bike, going to the beach, watching TV, playing on the computer,  swimming or walking  around.

My favourite is going to the beach.

1. Maria likes to ______ with her friends after school.

A. watch TV  

B. listen to music  

C. dance    

D. ride

2. Jack is in Grade ______ this year.

A. Seven      

B. Eight      

C. Nine      

D. Ten

3. ______ like to play football after school.

A. Jack and Tom      

B. Jack and Helen    

C. Tom and Peter

D. Tom and Helen

4. Helen usually goes to ______ after school.

A. the cinema    

B. the park    

C. her friend's home    

D. the beach

5. Which one is TRUE?

A. Helen and her friends enjoy fishing by the river.

B. Tom and Peter are students of Grade Eight.

C. Tom and his friends like to watch movies on the weekend.

D. Peter never plays with his friends after school.

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