叙述成本法应用的前提条件。
在常用的数据控件中，只需指定DataSource而不需指定DataField的控件有哪些？
有一台Y/Y-12接线的变压器，当低压侧BC相短路时，判断下列（）正确。 IB=IC，IA=0。 IA=IB=IC。 IA=IB，IC=0。
对于承受水平力的水利工程，应进行水平位移观测；有防渗要求的需进行（）的观测 正常蓄水位。 防洪高水位。 设计洪水位。 测压管水位。
You are at the client site working with a WebLogic Administrator who has to type Username and Password each time he/she starts an instance og Oracle WebLogic server and is quite annoyed by it. Please suggest a secure and optimal way to reduce the typing of username passwod during server startup （） Since Boot Identity file for server doesn’t exist， you recommend creating a script file that can automate the task of entering username and password。 Since Boot Identity file for server doesn’t exist， you recommend reinstalling the server。 Since Boot Identity file for server doesn’t exist， you recommend creating one as this file is referred for credentials。 Since Boot Identity file for server doesn’t exist， you recommend logging a support ticket with Oracle。
能够燃烧的低压液化气体共有（）种。
