Why is gas-freeing rarely required for LPG cargo tanks? （）
A. LPG is compatible with all cargos
B. LPG's high oxygen content makes it nonvolatile
Cargo tanks are inspected less frequently than on oil tankers
D. The cargo tanks are used for one type of cargo only
查看答案
为了保证防坠落辅助设备安全使用不应做到专人负责。
A. 正确
B. 错误
钢和铸铁都是铁碳合金，碳的质量分数（）的铁碳合金称为钢。
A. 大于2.11%
B. 小于2.11%
C. 小于6.67%
D. 大于6.67%
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