A Windows Communication Foundation (WCF) solution exposes the following service over a TCP binding.(Line numbers are included for reference only.) 01 [ServiceContract] 02 [ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple)] 03 public class DataAccessService 04 { 05 [OperationContract] 06 public void PutMessage(string message) 07 { 08 MessageDatabase.PutMessage(message); 09 } 10 [OperationContract] 11 pubic string[] SearchMessages(string search) 12 { 13 return MessageDatabase.SearchMessages(search); 14 } 15 } MessageDatabase supports a limited number of concurrent executions of its methods. You need to change the service to allow up to the maximum number of executions of the methods of MessageDatabase. This should be implemented without preventing customers from connecting to the service. What should you do?（） Change the service behavior as follows. [ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple, InstanceContextMode = InstanceContextMode.Single)]。 Change the service behavior as follows. [ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Single, InstanceContextMode = InstanceContextMode.PerSession)]。 Add a throttling behavior to the service, and configure the maxConcurrentCalls.。 Add a throttling behavior to the service, and configure the maxConcurrentSessions.。
按照建设项目基本建设程序要求，公路工程设计一定有（）阶段设计。 初步设计。 技术设计。 施工图设计。 变更设计。
人们将管理活动分为高、中、基3个层次，即（）、管理控制层、执行控制层。
教育观察研究有哪几种分类标准，其具体类型是什么？
根据《工伤保险条例》规定，职工因工死亡，其一次性工亡补助金标准是多少？
IP地址66.168.21.121是（）
