下列说法正确的是( ) A．要让放在河中的纸船逐渐靠近河岸，可向比纸船更远处掷石

发布时间：2017-04-23 16:08 │ 来源：www.tikuol.com

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问题：

下列说法正确的是(　　)

A．要让放在河中的纸船逐渐靠近河岸，可向比纸船更远处掷石子形成水波

B．两个在水中潜泳并且靠得较近的运动员也能利用语言交流，是声波在液体中传播的应用

C．宇航员在宇宙飞船里，击打船壁引起机械振动，不能在飞船体外形成波

D．以上说法全错

考点：机械波的形成和传播

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下图示意某动物体细胞(2N=4)有丝分裂的一个周期，下列对细胞周期的叙述，错误的是

[ ]

A．细胞周期的长短通常受温度的影响

B．细胞中含有4条染色体的时期是abd

C．调控细胞周期的基因发生突变，可导致细胞周期失控

D．完整的细胞周期是从标号1时开始，到下一个标号1时结束

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完形填空。
A long time ago, there was an emperor(皇帝). One day he told his horseman that if he could ride on his horse and 1 as much land area as he liked, he would give him the area of land he had covered. 2 enough, the horseman quickly jumped onto his horse and 3 as fast as possible to cover as much land area as he could. He 4 riding and riding, whipping the horse to go as fast as possible. Even when he was 5 or tired, he did not stop 6 he wanted to cover as much area as possible. When he at last covered a large amount of land, he was exhausted and was 7 . Then he asked himself, "Why did I 8 myself so hard to cover so much land area? Now I am dying and I only 9 a very small area to 10 myself." The above story is 10 to the journey of our 12 . We push ourselves very hard every day to make more 13 , to gain power or recognition. We neglect(疏忽,忘记) our 14 , time with our family and to appreciate(欣赏) the surrounding 15 and the things we love to do. One day 16 we look back, we will 17 that we don't really need that much, 18 then we cannot turn back time for what we have 19 . Life is not about making money. Life is definitely(肯定地) not about work! Work is only 20 to keep us living so as to enjoy the beauty and pleasures of life.
( )1. A. use ( )2. A. Good ( )3. A. rode ( )4. A. kept on ( )5. A. sad ( )6. A. but ( )7. A. sleeping ( )8. A. push ( )9. A. need ( )10. A. live ( )11. A. useful ( )12. A. future ( )13. A. friends ( )14. A. health ( )15. A. things ( )16. A. before ( )17. A. realize ( )18. A. or ( )19. A. saved ( )20. A. possible	B. cover B. Strange B. ran B. asked for B. excited B. so B. arguing B. make B. have B. bury B. certain B. past B. progress B. career B. condition B. when B. regret B. until B. missed B. probable	C. work C. Sure C. expanded C. gave up C. confused C. because C. dying C. destroy C. find C. support C. similar C. history C. discoveries C. honor C. people C. unless C. apologize C. however C. reduced C. necessary	D. get D. Interesting D. struggled D. succeeded in D. hungry D. if D. smiling D. prove D. show D. sleep D. special D. life D. money D. freedom D. beauty D. since D. explain D. but D. won D. suitable

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为保证疏散的安全，疏散楼梯间的平面和竖向布置应满足的一般要求中，表述不正确的是( )。

A．靠近标准层或防火分区的两端布置，应设置电梯层，便于双向疏散
B．靠近电梯间布置，将人们经常使用的路线和应急路线结合起来，利于快速疏散
C．楼梯间(除与地下室相连的楼梯、通向高层建筑避难层的楼梯外)竖向要保持上下直通，在各层的位置不应改变
D．疏散楼梯间和走道上的阶梯应符合安全疏散要求，不应采用螺旋楼梯和扇形踏步

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以下哪条措施对增强中空玻璃的保温性能基本无作用

A．增加两层玻璃的厚度
B．在两层玻璃的中间充惰性气体
C．用LOW—E玻璃代替普通玻璃
D．在两层玻璃的中间抽真空

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门窗贴脸，主要是为了加大门的立面尺寸，起到较好的装饰效果。( )

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