A study of the following websites prior to designing the questionnaire will be beneficial. Even now it's not late.
Likert scale: Definition from Answers.com
statistical consulting, likert data - Can Likert Scale Data ever be Continuous?
http://pubs.aged.tamu.edu/jae/pdf/Vol35/35-04-31.pdf
<link outdated-removed> ( Search On Cite | Search On Google )
All found at likert scale questions + statistical analysis - Google Search
Likert scale: Definition from Answers.com
statistical consulting, likert data - Can Likert Scale Data ever be Continuous?
http://pubs.aged.tamu.edu/jae/pdf/Vol35/35-04-31.pdf
<link outdated-removed> ( Search On Cite | Search On Google )
All found at likert scale questions + statistical analysis - Google Search