精选优质文档-倾情为你奉上 第一阶段在线作业 窗体顶端单选题 (共13道题) 1.(2.5分) The individual phases (gas, , liquid water, and solids) should be separated from each other as early as practical. A、liquid hydrocarbon B、free water C、sludge D、bubbles 我的答案:A 此题得分:2.5分 2.(2.5分) is the mainly compound in natural gas. A、Oxygen B、Methane C、Ethane D、Propane 我的答案:B 此题得分:2.5分 3.(2.5分) H2S and CO2 are very corrosive when is present.