单项选择题
A.±0.5mm B.±1.5mm C.±1.0mm D.±2.0mm
A.终拧1小时以后,24小时之前 B.初拧1小时以后,24小时之前 C.终拧24小时之前 D.初拧1小时以后
A.5% B.10% C.15% D.20%