1/2杯头内六角螺丝用（）六角匙装配合适。
A.3/8
B.1/2
C.1/4
D.8
参考答案：A
—Would you like to come to dinner this Sunday, Xiao Ming?
—________. [ ]
A. I'd love to, but I have lots of things to do.
B. Oh, no. That'll be too tired.
C. I'll stay at home.
D. Yes, please.
杆塔基础施工时，在地面上应留有（）高的防沉土台。
A、100mm
B、300mm
C、500mm
D、700mm
