单项选择题
A.0.15%B.0.25%C.0.30%D.0.35%
A.0.8B.0.7C.0.9D.0.85
A.380KN/m2B.400KN/m2C.360KN/m2D.480KN/m2
A.40KN/m2B.60KN/m2C.120KN/m2D.100KN/m2
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