一个人用手把一个质量为m1kg的物体由静止向上提起1m，这时

一个人用手把一个质量为m=1kg的物体由静止向上提起1m，这时物体的速度为2m/s，则下列说法中正确的是

A．手对物体所做的功为12J	B．合外力对物体所做的功为2J
C．合外力对物体所做的功为12J	D．物体克服重力所做的功为10J

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