工程投资、物资采购、宣传促销项目合同的签订及会签是如何规定的？
以下著名思想家与其著作对应关系正确的是（）。 ["孔子--《论语》","老子--《南华经》","庄子--《庄子》","孙武--《孙子兵法》","庄子--《逍遥游》"]
A check valve is another name for （）. ["a test valve","an inspection valve","a stop valve","a non-return valve"]
特种设备存在下列哪种情况，使用单位应当及时予以报废（） ["未经定期检验","存在安全隐患","超过安全技术规范规定使用年限","安全技术资料不齐"]
A butterfly valve consists basically of a disc pivoted across the bore of a ring body having the same radial dimensions as the pipe in which it is fitted.According to the above sentence, which of the following statements is not true?（） ["The diameter of a disc is the same as the outer diameter of the pipe","We can infer that the valve is opened or closed by rotating the spindle","A butterfly valve comprises a disc and a ring body","The profile of the butterfly valve is a ring body"]
使用全价配合饲料有什么优点？
