下列项目中影响车削零件位置公差的主要因素是（）
A、零件装夹
B、工艺系统精度
C、刀具几何角度
D、切削参数
参考答案：A
They ______ at six in the evening. [ ]
A. do homeworks
B. do their homework
C. do his homework
D. do their homeworks
如何利用内部收益率进行多方案比较
