Dear Sir or Madam,

With reference to your advertisement in China Daily on November 28th, 2008, I am writing to express my interest in applying for the captioned post.

I am presently a programmer at Success Securities. Ltd., and my 2-year contract will expire soon. By applying for the post I am looking forward to switching to a larger, more sophisticated and more computerized company so that I can enrich myself to meet the challenges that a large company poses.

Please refer to the enclosed resume for the technical details of my past duties. I would be available for an interview at your convenience. Thank you for your attention to this application.

×××

When does he find the advertisement
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升降机内固定一光滑斜面体B，斜面上端固定一弹簧，弹簧下端连一质量为m的物体A，开始时系统处于静止状态。从某时刻起，升降机以加速度a开始匀加速上升，在以后的上升高度为h的过程中，下列说法中正确的是

A．物体A相对斜面静止不动

B．物体A的机械能增加量等于斜面对A做的功

C．物体A的重力势能增加量为mgh

D．物体A、B及弹簧的机械能增加量等于升降机对B做的功