Asp.net MVC2

Question

Hai all,

I have 3 radio buttons in my asp.net mvc2  form ............................

and i want to get the cheked value from like Y or N

here is my code 

<%:Html.RadioButton("Y", "is_admin",true)%>Is Administrator<br />

                                       <%:Html.RadioButton("Y","is_operator", false)%>Is Data Operator<br />

                                        <%:Html.RadioButton("Y","is_approver", false)%>Is Approver<br />

Help me any one .................i am a trainee programmer new to IT........