单项选择题
A.2#复合锂基脂 B.50#机油 C.二硫化钼 D.汽机油
A.115 B.250 C.500 D.1150
A.精矿 B.重油 C.白灰 D.煤、富矿
A.20% B.10% C.15% D.30%
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