A:魏国
B:秦国
C:楚国
D:齐国
My mother ____ (not cook) every evening.
The movie wasn't _____. He fell asleep halfway through it.
如图所示,用沿斜面向上2N的拉力,把重为5N的物体匀速拉到高处,请画出拉力的示意图和物体重力对支点O的力臂