单项选择题
A.1000 B.1200 C.1400 D.1600
A.石墨钙基润滑脂 B.钠基润滑脂 C.复合铝基润滑脂 D.机械油或液压油
A.1/2 B.1/3 C.1/4 D.1/5
A.50% B.60% C.70% D.80%
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