A.C15 B.C20 C.C25 D.C30
A.-5~40 B.0~40 C.-5~50 D.0~50
A.加 B.减 C.乘 D.依情况而定
A.fcu=1.56F+2.35 B.fcu=2.76F-11.54 C.fcu=1.28F-0.64 D.fcu=2.35+1.38
A.2mm B.4mm C.6mm D.8mm