单项选择题
A.5~10L/s B.15~20L/s C.20L/s D.10~15L/s
A.30 B.20 C.60 D.25
A.-10~55℃ B.-21~55℃ C.4~55℃-4~55℃
A.2% B.3% C.4% D.6%
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