在PowerPoint 2003中，如果要使多个图形对象的中心点对齐，应该在“绘图”工具栏“绘图”列表中选择（）。 ["水平居中","水平居中、垂直居中两者皆选","把它们拖在一块","垂直居中"]
属于国家立法强制实行的政府行为、全体劳动者必须参加的养老保险类型是（）。 ["基本养老保险","补充养老保险","个人储蓄性养老保险","商业养老保险"]
Diesel engine control can be obtained by the bridge （）. ["at any time","only after the engine room control station is switched to “bridge control”","whenever the secondary station is switched to "bridge control"","with the approval of the chief engineer only"]
雇佣双方劳动关系建立的标志是（）。 ["劳动报酬","劳动合同","劳动法规","劳动能力"]
为了使焦炭在炭化室内同时成熟，炭化室宽每增加一毫米，温度变化（） ["1.5℃～2℃","0.5℃～1℃","1.2℃～1.5℃"]
氢气冷却塔前氢气总管压力突然过低原因分析及处理措施有哪些？
