题目

如图所示,一轻弹簧的左端固定在墙壁上,右端连接一个小球,小球放置在光滑水平地面上。弹簧处于原长时,小球在位置O。将小球拉至位置A(弹簧处于弹性限度内),然后由静止释放。释放后,小球从A第一次运动到O的过程中,小球与弹簧所组成系统的机械能( )A.保持不变B.逐渐减小C.逐渐增大D.先增大后减小On hearing the news, she rushed out without hesitation,        her handbag         on the sofa and         in the distance.     A.left; lied; disappeared  B.leaving; lying; disappeared     C.leaving; laying; disappeared D.left; lying; disappearing
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