单项选择题
A.10% B.15% C.20% D.25%
A.1.2mm B.1.5mm C.1.6mm D.2mm
A.400—500mm B.500—600mm C.200—300mm D.300—400mm
A.4mm;4mm B.5mm;5mm C.6mm;5mm D.7mm;4mm
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