Crater Lake lies in the caldera of an ancient volcano called Mount Mazama that collapsed 7,700 years ago. The lake is the deepest in the United States and is noted for its vivid blue color and water clarity. Wizard Island and the Phantom Ship are more recent volcanic formations within the caldera. As the lake has no inlets or outlets, it is replenished only by precipitation
USNPs
Optimized studying based on the forgetting curve vastly improves memorization. - What is reminDO?
Memorize