单项选择题
A.变形B.扭曲C.正应力D.剪切应力
A.宽13mm,齿距0.8mmB.宽12mm,齿距0.8mmC.宽12mm,齿距1.0mmD.厚0.64mm,齿距1.8mm
A.10~70B.20~100C.30~120D.40~100