Proper Syntax to pass multiple parameters on querystring?

 Below is my code to pass one value on a querystring.
 
<asp:HyperLink ID="productImgLNK" runat="server" NavigateUrl='<%# Eval("invID", "productDetail.aspx?invID={0}") %>' Text='<%# Eval("invItemName") %>' ImageUrl='<%# Eval("invThumbImg","~/images/inventory/{0}") %>'></asp:HyperLink>
 
I want to also pass the catID and subcatID.
How would I edit my NavigateUrl to make this happen?
TRU
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