an image from the US government EPA "Sunwise" program. I converted it from PDF format, and removed all the "sunwise" logos. the source link is here - http://www.epa.gov/sunwise/doc/mission_story.pdf
指向董事會
blackboard、board、cartoon、classroom、epa、epa sunwise、group、People、point、whiteboard
黑板、板、動畫片、課堂、EPA、epa sunwise、組、人、點、白板
資料來源：openclipart ( https://openclipart.org/ )