室外氢气管道应于防雷接地装置相连，接地电阻不应大于（）欧姆。 30。 20。 40。
You use Microsoft .NET Framework 4 to create a Windows Presentation Foundation (WPF) application. You create a custom control named Wheel. You need to ensure that the Speed property of Wheel can be animated. What should you do?（） Inherit the DependencyObject class.。 Declare the Speed property as a dependency property.。 Declare an animation of the Speed property from within the code-behind file.。 Implement the System.Windows.Media.Animation.IAnimatable interface with the Wheel class.。
You need to design an authentication strategy for users of portable computers. Your solution must meet business requirements. What should you do？（） Issue smart cards and smart card readers to all portable computer users. Configure the domain to require smart cards for login and to log off users who remote their smart cards。 Configure the portable computers to connect to only wireless networks that use Wired Equivalent Privacy （WEP）. Install digital certificates on all portable computers。 Install computer certificates on all portable computers. Configure all portable computers to respond to requests for IPSec encryption。 Install biometric authentication devices on all portable computers. Configure the Default Domain Policy GPO to require complex passwords for all user。
You have an Exchange Server 2010 Hub Transport server named Hub1. You install an application on a third-party server named Server1. You discover that the application cannot authenticate to remote servers. You need to ensure that the application can relay e-mail messages by using Hub1. What should you do？（） .Create a new Send connector.Add the TCP/IP address of Server1 to the Send connector .Modify the permissions for the Send connector。 .Create a new Receive connector.Add the TCP/IP address of Server1 to the Receive connector .Modify the permissions for the Receive connector。 .Add the TCP/IP address of Server1 to the default Receive connector .Create a message classification.Create a transport rule。 .Add the TCP/IP address of Server1 to the Client Receive connector.Create a remote domain.Create a transport rule。
呼叫中心对外面向用户，对内与整个企业相联系，是企业的（） 支出中心。 收入中心。 数据中心。 计算中心。
无杀虫作用的药物是（）
