* Ministry of Education\The book sector\Biology book Form 1st secondary.

*Images: Microsoft Encarta.

*Buttons: www.absolutedesigns.com

*www.susku.edu/satsci/feb21.htm

*www.epa.gov/acidrain/effect/envben.html

*www.dnr.state.wi.us/org/aw/air/health/acidrain/htm