无凸缘筒形压延件按等面积计算的方法是将它分成四个简单的几何体并分别求面积。()
参考答案:错
No one asked for me while I was out, ___?
A.didn't he
B.did they
C.did it
D.do they
过盈配合是一种固定连接,要求有正确的相互位置和紧固性,还要求装配时不损伤机件的强度和精度,装入简便和迅速。