单项选择题
A.≤3.8s B.≤5.5s C.≤6.5s D.≤7.5s
A.75° B.90° C.105° D.120°
A.0.5mm B.0.6mm C.0.7mm D.0.8mm
A.1mm B.2mm C.3mm D.4mm
微信扫一扫,加关注免费搜题
