[单选] You have an SQL query that takes one minute to execute. You use the following code segment to execute the SQL query asynchronously.Dim ar As IAsyncResult = cmd.BeginExecuteReader()You need to execute a method named DoWork() that takes one second to run while the SQL query is executing. DoWork() must run as many times as possible while the SQL query is executing. Which code segment should you use?（）

Your company has an Active Directory domain named ad.contoso.com. The domain has two domain   controllers named DC1 and DC2. Both domain controllers have the DNS Server server role installed.   You install a new DNS server named DNS1.contoso.com on the perimeter network. You configure DC1 to   forward all unresolved name requests to DNS1.contoso.com.   You discover that the DNS forwarding option is unavailable on DC2.   You need to configure DNS forwarding on the DC2 server to point to the DNS1.contoso.com server.    Which two actions should you perform（） Clear the DNS cache on DC2.。 Delete the Root zone on DC2.。 Configure conditional forwarding on DC2.。 Configure the Listen On address on DC2.。 血缘家族 27系列EPROM存储的数据是（）可擦除的。 不。 电。 紫外线。 融断器。 你在 Certkiller.com 做应用程序的开发工作。，Certkiller.com，让你在开发应用程序处理Certkiller.com 停车场通行证。应用程序必须存储和检索使用车辆识别号码 (VIN) 的车辆信息。您需要使用正确的代码，以确保类型安全。你应该做什么？（） 。 。 。 。 钱穆在评唐朝的三省制时指出：“一切政府法令，须用皇帝诏书名义颁布者，事先由政事堂开会议决。送进皇宫画一敕字，然后由政事堂盖印中书、门下之章发下。没有政事堂印，即算不得诏书，在法律上没有合法地位。”由此可见，唐朝的政事堂（）。 使三省体制走向完备。 是尚书省的代替机构。 发挥重要的决策作用。 有利于提高行政效率。 You have an SQL query that takes one minute to execute. You use the following code segment to execute the SQL query asynchronously.Dim ar As IAsyncResult = cmd.BeginExecuteReader()You need to execute a method named DoWork() that takes one second to run while the SQL query is executing. DoWork() must run as many times as possible while the SQL query is executing. Which code segment should you use?（）