InfoPath Dev

I have a drop down box that references a sharepoint list to pull a list of employee names. In conjunction with the name, the list also contains their email address. When I select their name from the drop down list, I want their name to populate into the email address field.

I have a designed infopath form that has a total of 13 questions. The form starts with 9 questions, and based upon the input of 2 questions it can be up to 13 questions long. The questions get introduced into the form in sections, based upon the input of one of the 3 trigger questions. My problem lies in that I have to get a percentage based upon ...