单项选择题
A.>1000 B.500-1000 C.<500 D.>5000
A.烷烃 B.二烯烃 C.芳烃 D.稠环化合物
A.1-3% B.2-5% C.4-10% D.12%
A.3% B.1.5% C.0.5% D.0.05%
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