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【简答题】
Section B Directions : In this section, you will hear 3 short passages. Passage One Questions 16 to 18 are based on the passage you have just heard. 16. A. No one knows for sure when they came into being. B. No one knows exactly where they were first made. C. No one knows for what purpose they were invented. D. No one knows what they will look like in the future. 17. A. Measure the speed of wind. B. Give warnings of danger. C. Pass on secret messages. D. Carry ropes across rivers. 18. A. To find out the strength of silk for kites. B. To test the effects of the lightning rod. C. To prove that lightning is electricity. D. To protect houses against lightning.
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皮皮学刷刷变学霸
举一反三
【多选题】站立的注意事项正确的是( )
A.
不要两腿交叉站立
B.
将身体的重心明显地移到一侧，只用一条腿支撑着身体
C.
将手叉在裤袋里面
D.
男子双脚左右开立时，注意两脚之间的距离不可过大，不要挺腹翘臀
【简答题】咀嚼肌由 翼内肌 、 和 组成。
【单选题】Call you tell me___ ?
A.
where are you from
B.
where do you come from
C.
where you from
D.
where you come from
【简答题】事件2中，安全检查的内容不完整，请补充。
【多选题】光电效应现象的发现和爱因斯坦的光子说的建立,人们才逐渐意识到光既有波动性,又具有粒子性,以下说法中正确的 是 ( )
A.
牛顿用微粒说可成功地解释光的直进和反射
B.
惠更斯的波动说可以成功地解释反射、折射、叠加等现象
C.
牛顿的微粒说也能解释光干涉现象
D.
惠更斯的波动说在解释光的直线传播产生影等现象遇到了困难
【简答题】3-10、假设变量a、b和c均为整型,以下语句借助中间变量t把a、b和c中的值进行交换,即:把b中的值给a,把c中的值给b,把a中的值的给c。例如:交换前,a=10,b=20,c=30;交换后,a=20,b=30,c=10。请填空。_______; a=b; b=c;__________;
【简答题】Read and write. (根据图片内容，将单词补充完整)
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