"One science question"

Both RPM and Chad beat me to posting this survey [edited to add: and Janet too! Freakin’ quick triggers…], which I’ve had in my drafts box for a week. So, before absolutely everyone else beats me to it, I thought I’d pose the questions to y’all, and see how you would answer the question, “What is one science question every high school graduate should be able to answer?”

(Continued at Aetiology)