About what share of Earth's unfrozen freshwater sits in a single lake, Siberia's Lake Baikal?

The answer

UNESCO calls Baikal the world's oldest and deepest lake, about 25 million years old and 1,700 m down, holding roughly 20% of the planet's unfrozen freshwater reserve. One rift lake, one-fifth of the easy-to-drink supply.

Correct answer: About 20%