题干

如图所示表示的是四冲程汽油机的____冲程,该汽油机的飞轮转速为 1200r/min,则1s内汽油机对外做功____次.

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压缩,10

同类题1

完形填空

    The leaves fluttered (飘动)over Josh's head. The park near his home had always been one of Josh's1 places. ①He liked to watch the colors of the trees glow (闪耀)in the sunlight,2the golden trees. It was the same color as his trumpet (小号).He smiled when he 3 the music the leaves made. Josh sat down and looked at his watch. His father would meet him in a few 4 for their first practice in the park.

    Josh and his family lived in an apartment building. When Josh first began playing the trumpet, he5 in his own living room. Then the family next door had a new baby. To avoid6the baby, Josh would 7his practice time in the park. His father told him it would be good to practice in a wide,open8like the park. The baby next door would be able to sleep 9, but Josh was not very happy with the10 . He enjoyed visiting the park,but he didn't want to practice there. He was 11that he would embarrass (使……难堪)himself in a pubic place if he played the wrong notes (音符).He didn't want people to12him as he played in the middle of the park.

    Josh's father was a great trumpet player, who once played in a jazz band. He couldn't possibly understand how13 it would be to practice in the park!

    His father came over and14Josh's daydream. "Josh, are you ready to practice?" He sat down and 15 his own trumpet from its case. He held the trumpet to his16and began to play. The beautiful music floated into the blue afternoon sky.

    Josh looked up at the golden trees. The leaves17 to be dancing to the tune his father was playing. Josh felt 18as he watched the people walking by and smiling at his father.

    He 19 to play like that. Josh put his trumpet to his mouth and blew. He had such a great time that he didn't 20 if he played a few bad notes. Now he and his neighbors could all be happy.

同类题3

阅读下列材料,回答问题。

材料一  第一次世界大战以前,资本主义各国实行金本位制,即各国以立法手段规定黄金纸币的价格(即:各国通过立法规定本国货币的含金量),在此基础上,形成各国货币之间的汇率关系……各国货币之间的汇率总是围绕黄金平价上下波动。

材料二  1944年44国达成了布雷顿森林协定,根据协议成立国际货币基金组织。“按照国际货币基金组织协定,成员目需承担义务,自协定生效后的3—5年过渡时期终了之日起,废除外汇管制,实行货币自由兑换……以l盎司黄金换35美元的比价为基础,确定成立各成员国货币之间的汇率结构……成员国不得擅自改变汇率……美国在该体系中处于支配地位。”

    ——以上材料摘自王在帮《布雷顿森林体系的兴衰》

材料三  1959年,美国的外债接近她的官方黄金储备的总价值,两者均为200亿美元左右。到1967年,美国总的海外流动债务已经急剧上升到360亿美元,然而其黄金储备已经垂直下跌到120亿美元,只有债务总量的三分之一。l961年1月,肯尼迪总统第一次向参众两院做演讲时指出:“自从1958年以来,我们花费或者投资在国外的美元与重新回到我们手中的美元之间的差额大幅增加。在过去的三年中,我们的贸易赤字总额增加了将近110亿美元,国外美元持有者把它们转换成了黄金,数目如此之大,将导致我们近50亿美元的黄金储备流失。” 

    ——美威廉·恩道尔《石油战争》

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