But for the fact that China ____ also af
题型：选择题
问题：
But for the fact that China ____ also affected by the global economic crisis, we ____ fewer unemployed workers now.
A．is; would have
B．were; would have
C．was; would have had
D．is; would have had
题型：选择题
如图所示，光滑水平面上有大小相同的A、B两球在同一直线上运动。两球质量关系为mB＝2mA，规定向右为正方向，A球的动量为6kg·m/s ，B两球的动量为4kg·m/s，运动中两球发生碰撞，碰撞后A球的动量增量为-4kg·m/s，则左方是________球，碰撞后A、B两球速度大小之比为________。
