Image credits and licenses:
Energy: Copyright 2011; (with changes) "Up close with my solar panels" by Michael Mazengarb licensed under CC BY-NC 2.0
Sustainability: Copyright 2014; (with changes) "Muir Woods Ocean View Trail" by Miguel Vieira under CC BY 2.0
Water: Copyright 2013; (with changes) "Calm Waters" by Jocelyn Kinghorn licensed under CC BY-SA 2.0
Food: Copyright 2012; (with changes) "Corn Field" by United Soybean Board licensed under CC BY 2.0
Use of images does not imply endorsement or support by the image creator(s).