With the form opened for editing go to the Options tab. In Options select Email Notifications and check the checkbox labeled "Send email notifications when submissions are received". In addition there are checkboxes for enabling "Include submitted data" and "Include empty fields". These checkboxes are enabled when the feature is turned on.
I didn't realize that I would have to pay to get email responses. It's too bad that Adobe doesn't feel the need to be competitive with so many other free forms out there.
Thanks for the response.