轴类零件的毛坯形式不同,若毛坯余量不均匀,粗车时应选用()。
A.90°偏刀
B.90°左偏刀
C.60°螺纹车刀
D.75°车刀
参考答案:D
Studies show that students are more ______ to be addicted to playing computer games if they always
play them before computer screens every day. [ ]
A. possible
B. probable
C. likely
D. perhaps
商品最本质的因素是()。
A.价值
B.价格
C.使用价值
D.交换价值