Just append those two strings.
<a href="<%= Application["ImgSection"].ToString() + "/ACR Total TPDoc Volume.jpg" %>" >ACR Total TPDoc</a>
Consider the ImgSection in Codeproject.com
Application["ImgSection"] = "http://www.codeproject.com/images";
Then your link will looks like below
ACR Total TPDoc Image (Look at the status bar for the sample URL while mouse over this link)