如图所示，一轻质弹簧下端与固定挡板相连，上端与放在倾角θ=30°的光滑斜面上的小车A相接触（未连接）．小车A质量M=3kg，内有质量m₀=1kg的砝码，小车A又与一跨过定滑轮的不可伸长的轻绳一端相连，绳另一端悬挂着物体B，B的下面又挂着物体C，B和C质量均为m=1kg，A、B、C均处于静止状态．现剪断B和C之间的绳子，则A和B开始做振幅为d=5cm的简谐运动，斜面足够长且始终静止．（g取10m/s²）试求：

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下列说法不正确的是（　　）

《说文解字》：“禾，嘉谷也，二月始生，八月而熟，得时之中，故谓之和”。农耕时代的人们普遍认为，禾苗是天地万物和谐的产物，禾苗是自然协调的象征。以上材料说明：①农耕时代所产生的观念，反映了该时代社会生产生活的图景   ②农耕社会的生产实践，是顺应该时代观念的需要而产生的  ③禾苗被赋予自然协调的象征，源于农耕时代的生产活动 ④禾苗被赋予自然协调的象征，这一观念的产生与农耕社会无必然联系

夏季我国最凉爽的地区（    ）

Dear Sally,
      I really need your help. I'm feeling ____ (沮丧的) these days, because I get so many____ (问题). I'm not a good-looking girl and I'm not good at studying, ____  (也).Some of my classmates always make joke of the way I ____ (穿). They think my clothes are all out of style,  ____  (甚至 )my best friend, Lily. I try everything I can, but nothing____ (似乎) to work. What’s more, in my family, there's a more ____ (严重的) problem. My parents____ (争吵) with each other, and they haven’t talked to each other now.And I ____ (失败) my Chinese test yesterday. Can you give me some ____ (建议)?
Yours
A lonely girl
There will be more tall ____ (build) in our city in the future.
Liu Yang is one of the greatest national____  (hero) in China.
 Lucy____ (shop) when there was a fire (火灾) in the mall.
They walked home together in s____ .
All my classmates went to the park e____  me.