制冷系统的制冷剂具有毒性、窒息和（）的特点 ["酸性","碱性","易燃"]
轨距（轮距）以什么字母表示（） ["K","L","S"]
连续审计时，注册会计师在财务报表审计和内部控制审计中都可以考虑以前审计中所了解和测试的情况，但在执行内部控制审计时，应当在每（）年度审计中测试内部控制，但是对自动化应用控制在满足特定条件情况下所采用的与基准相比较策略除外。 ["A.一 ","B.二 ","C.三 ","D.四"]
无规则网络学说
A developer has created a web application that includes a servlet for each use case in the application.These servlets have become rather difficult to maintain because the request processing methods havebecome very large. There is also common processing code in many servlets because these use cases arevery similar. Which two design patterns can be used together to refactor and simplify this web application？（） ["Proxy","View Helper","Front Controller","Session Facade","Business Delegate","Model-View-Controller"]
某企业200X年1～5月份的某项混合成本与有关产量的历史资料如下表：
要求：利用高低点法建立相应的成本模型。
