多项选择题 You are developing an application that connects to a Microsoft SQL Server database using the SqlConnection object. Your connection objects are being pooled. As the pool fills up, connection requests are queued. Some connection requests are rejected. You need to ensure that the application releases connections back to the pool as soon as possible. Also, you need to decrease the likelihood that connection requests will be rejected. Which three actions should you perform?（）

单项选择题 You develop a Web application. Your application contains two settings in the Web.config file. You deploy your application to production. You need to modify the application settings in the production environment without manually editing the XML markup in the Web.config file. What should you do? （）

单项选择题 You create a Web Form that contains a button named btnCancel that enables users to exit the page. When users click this button, validation must not occur. During testing you learn that clicking the Cancel button does not enable users to exit the page. You need to ensure that users can always exit the page. What should you do?（）