How do you determine which of a group of radio buttons has been selected?

I am a VB6 Windows programmer trying to learn VB.net website programming.  I have a group of radio buttons in a panel.  I have also applied a group name to them.  Either of those things I believe accomplishes the purpose of forcing users to select just one of the group.  But is there some quick and slick way to determine which button  has been selected?  I have 16 of these groups.  I need to determine when all 16 groups have a radio button selected, then I need to determine which button has been selected for each group.  I don't know where to start, and I am not having any luck finding what I need with web searches.  Can anyone point me in the right direction?

<asp:Panel ID="Panel1" runat="server" Width="320px"><asp:RadioButton ID="rad10" runat="server" Font-Size="X-Small" GroupName="Q1" 
                           Text="0" Width="40px" /><asp:RadioButton ID="rad11" runat="server" Font-Size="X-Small" GroupName="Q1" 
                           Text="1" Width="40px" /><asp:RadioButton ID="rad12" runat="server" Font-Size="X-Small" GroupName="Q1" 
                           Text="2" Width="40px" /><asp:RadioButton ID="rad13" runat="server" Font-Size="X-Small" GroupName="Q1" 
                           Text="3" Width="40px" /><asp:RadioButton ID="rad14" runat="server" Font-Size="X-Small" GroupName="Q1" 
                           Text="4" Width="40px" /><asp:RadioButton ID="rad15" runat="server" Font-Size="X-Small" GroupName="Q1" 
                           Text="5" Width="40px" /><asp:RadioButton ID="rad16" runat="server" Font-Size="X-Small" GroupName="Q1" 
                           Text="6" Width="40px" /><asp:TextBox ID="txtQ1" runat="server" Visible="False" Width="20px"></asp:TextBox></asp:Panel>

LouatMonaco