The small village, which is l____(位于) at the foot of the mountain, has become a holiday resort.
以下说法中正确的是( )
如图所示,动滑轮重0.5N,物体重3.5N,当OA=2OB时,为使轻质杠杆保持水平平衡、在A端所加的力应为(不计摩擦)( )