When you're thirsty for a drink of water, you probably turn on the tap, or open a container of bottled water.
You may take for granted that the water you drink is safe and free of contaminants. But the quality of water—and even its safety—can vary from place to place, depending on the water source and how it was treated. Find out more about drinking water
by taking this quiz, based on information from the U.S. Environmental Protection Agency (EPA).