桡神经损伤多见于
A．肱骨髁上伸直型骨折B．肱骨干骨折C．桡骨远端骨折D．锁骨骨折E．尺骨上1/3骨折
参考答案：B
We ______ here at lunch time; we were delayed at the airport, though. [ ]
A. could be
B. would stay
C. must have been
D. would have been
弹簧测力计沿水平方向拉着木块大水平木板上做匀速运动时，弹簧测力计的示数为0.5N，此时摩擦力的大小也为______N．若拉力增大，当弹簧测力计的为0.8N时，木块受到的滑动摩擦力的大小为______N．
