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淘气的小狗向下拉动了绳子,没有想到这根绳子牵引着5只球。请问:哪些球会上升,哪些会下降? (积分值:0.5分)
Naughty puppy pulled down the rope, did not think this rope traction 5 ball. Excuse me: Which ball will rise, which will drop? (Integral value: 0.5 points)