单项选择题
A.歪斜B.磨损C.间隙小D.间隙大
A.0.5~0.7B.0.3~0.6C.0.6~0.8D.0.4~0.7
A.0.5~0.7 B.0.3~0.6 C.0.6~0.8 D.0.4~0.7