如图，滑板运动员在平台上从A位置水平滑出，在落到C位置时，运动员通过调整姿势进行

发布时间：2017-05-23 17:31 │ 来源：www.tikuol.com

题型：计算题

问题：

如图，滑板运动员在平台上从A位置水平滑出，在落到C位置时，运动员通过调整姿势进行缓冲使自己只保留沿圆轨道切向速度而不弹起。圆轨道光滑，O点为圆轨道圆心，C、E为等高点，OD为竖直线。已知：运动员与滑板的总质量M=90kg，AB=20m，BC=30m，

∠COE=60⁰，g=10m/s²，cos27^o=0.9996求：

（1）滑板运动员从A位置滑出时的速度大小。

（2）滑板运动员从E位置滑出时的速度大小（结果保留两位小数）。

考点：平抛运动

题型：计算题

患儿，日龄5天，因"腹泻2天伴尿少1天"入院，查血气分析，最容易出现以下哪种酸碱失衡（）

A.呼吸性碱中毒

B.代谢性酸中毒合并呼吸性酸中毒

C.代谢性碱中毒

D.代谢性酸中毒

E.呼吸性酸中毒

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题型：计算题

完型填空。

     Returning from a trip overseas, I sensed that something was wrong between Keith and me. So I asked him,
"Keith, have I done anything that really   1 your feeling?"
     Immediately, he said, "Yes. Last Christmas you promised us a special   2   that I really wanted but you   3
gave it to me."
     The   4   was that I'd completely forgotten about it. I   5 , "Is there anything else I've done wrong, but didn't
apologize for?"
     Again, his   6   was immediate, "Remember last Christmas when Mom said you had to go to the   7   because
Stephen was going to be born? You left us at home and   8   in a hurry. Remember?"
     "Well, you left and   9   the suitcase." I couldn't believe he  10  all the details! "After you came back from the
hospital you were  11 . When you got home, the suitcase had been opened and  12  had been thrown all over the
place. And you  13  me."
     "And you didn't do it?" I asked. "No, I didn't. I was just searching for my gift."
     My heart sank. I felt  14 . I hugged Keith and asked him to  15  me. His honesty made me think of our other
son, Kevin. Maybe I'd hurt his feelings, too. I went to ask him the  16  question. Kevin's answer was as
immediate as his  17 , "Last Christmas you  18  us a special toy, but you forgot about it."
       19  Christmas had passed, I took my two sons to the store that day and bought them what I had promised.
The  20  thing wasn't the toy. The problem was I'd made a promise too lightly and didn't keep it as their father.

( )1. A. showed
( )2. A. toy
( )3. A. never
( )4. A. challenge
( )5. A. continued
( )6. A. suggestion
( )7. A. hospital
( )8. A. settled down
( )9. A. replaced
( )10. A. remembered
( )11. A. satisfied
( )12. A. nothing
( )13. A. praised
( )14. A. inspired
( )15. A. support
( )16. A. same
( )17. A. mother’s
( )18. A. bought
( )19. A. Though
( )20. A. strange

B. attended
B. book
B. often
B. message
B. apologized
B. blame
B. church
B. set off
B. forgot
B. imagined
B. worried
B. somebody
B. punished
B. hopeless
B. criticize
B. direct
B. father’s
B. borrowed
B. Because
B. interesting

C. hurt
C. picture
C. always
C. idea
C. complained
C. action
C. school
C. went on
C. brought
C. discovered
C. happy
C. everything
C. helped
C. terrible
C. suspect
C. easy
C. sister’s
C. promised
C. Since
C. difficult

D. expressed
D. candy
D. ever
D. fact
D. explained
D. answer
D. garden
D. got up
D. opened
D. knew
D. angry
D. nobody
D. educated
D. encouraged
D. forgive
D. funny
D. brother’s
D. left
D. Until
D. important

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题型：计算题

既可化湿，又可发表解暑的中药是（）

A.佩兰

B.苍术

C.羌活

D.砂仁

E.独活

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题型：计算题

油气井“三高”井是指具有（）特征的井。

A.高产

B.高压

C.高含硫化氢

D.高温

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题型：计算题

关于人工流产术中宫颈裂伤，说法错误的是（）。

A.宫颈裂伤轻者使宫颈内口组织撕裂；重者全宫颈裂伤甚至延长至子宫下段

B.暴力扩张或扩张器跳号扩张所致

C.宫颈息肉所致

D.未生育者宫颈往往较坚韧而脆弱，因而较易裂伤

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