________ covers 0.78% of earth's surface.

Explanation

To answer the question, "________ covers 0.78% of earth's surface," we can follow these steps:

1. **Understand the Earth's Surface Composition**: The Earth's surface is primarily made up of water, with about 71% being covered by water.

2. **Differentiate Between Types of Water**: Out of the total water on Earth, about 97% is salty water found in oceans and seas, while only about 3% is fresh water.

3. **Analyze Fresh Water Distribution**: Among the fresh water, approximately 2% is frozen in glaciers and ice caps, which leaves us with about 1% of the Earth's surface being fresh water in liquid form.

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