A.100mm B.120mm C.140mm D.160mm
A.梁高h(yuǎn)=350mm B.梁高h(yuǎn)=400mm C.梁高h(yuǎn)=450mm D.梁高h(yuǎn)=550mm
A.la B.1.1la C.1.1la D.1.3la