多项选择题 You want to create a valid directory structure for your Java EE web application， and your application usestag files and a JAR file. Which three must be located directly in your WEB-INF directory（NOT in asubdirectory of WEB-INF）？（）

单项选择题 You have built a web application with tight security. Several directories of your webapp are used for internal purposes and you have overridden the default servlet to send an HTTP 403 status code for any request thatmaps to one of these directories. During testing， the Quality Assurance director decided that they did NOTlike seeing the bare response page generated by Firefox and Internet Explorer. The director recommendedthat the webapp should return a more user-friendly web page that has the same look-and-feel as the webapp plus links to the webapp’s search engine. You have created this JSP page in the /WEB-INF/jsps/error403.jsp file. You do NOT want to alter the complex logic of the default servlet. How can you declarethat the web container must send this JSP page whenever a 403 status is generated？（）

单项选择题 Click the Exhibit button. As a maintenance feature， you have created this servlet to allow you to upload and remove files on yourweb server. Unfortunately， while testing this servlet， you try to upload a file using an HTTP request and onthis servlet， the web container returns a 404 status. What is wrong with this servlet？（）