A.1mm B.2mm C.3mm D.4mm
A.键宽 B.0.4mm C.键上表面 D.键下表面
A、20kPa B、30kPa C、40kpa D、50kpa
A.34.5~35.5mm B.41~-45mm C.31.5~34mm D.65~68.5mm
A.50mm B.135mm C.17mm D.275mm
A.10kPa B.20kPa C.30kPa D.40kPa
A.仿宋体 B.宋体 C.隶体 D.楷体