The kids are back at school, but that doesn't mean you can't take a quiz ... this one about groundwater. The U.S. Geological Survey's quiz on groundwater is challenging, but you'll be an expert after reading the detailed explanations of what you got wrong.
Here's a visual aid...
This RSC member didn't do too well. Try it out yourself and see how you did! As an incentive, the USGS claims that if you take the quiz "you'll find that you can amaze your friends with little-known facts at the next party."