单项选择题
A.用自来水清洗 B.用蒸馏水清洗 C.蒸汽清洗 D.烘干
A.≤0.5mg/L B.≤0.1mg/L C.≤0.05mg/L D.≤0.01mg/L
A.0～10mg/L B.0～30mg/L C.10～30mg/L D.30～50mg/L
A.10s B.20s C.30s D.60s
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