单项选择题
A.15% B.20% C.25% D.30%
A.≥0.97 B.≥0.96 C.≥0.95 D.≥0.94
A.30~50mm B.50~100mm C.100~150mm D.150~200mm
A.100~200mm B.200~300mm C.300~500mm D.400~600mm
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