1. How much of the total water at earth's surface is fresh water?

2. Of all the freshwater at the earth's surface, what percent is found as ice and glaciers?
3. What percent of all freshwater is groundwater?
4. What percent of the rainfall that falls on continents is returned to the oceans as runoff? What percent evaporates?

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To find the answers to these questions, we can refer to the provided link, which contains information on various water-related topics. Let's explore each question step by step:

1. The first question is asking about the percentage of fresh water compared to the total water at the earth's surface. To find this, we can look for information on the distribution of water on Earth. The link provided might contain the necessary data.

2. The second question asks about the percentage of freshwater that is in the form of ice and glaciers. To determine this, we need to find the amount of freshwater stored in ice and glaciers and calculate it as a percentage of the total freshwater on Earth.

3. The third question is about the percentage of all freshwater that exists as groundwater. We can try to find this information in the provided link. Groundwater is a significant source of freshwater, so it is essential to understand its share.

4. The fourth question asks about the percentage of rainfall that returns to the oceans as runoff and the percentage that evaporates. To find this, we can refer to the information available on the provided link.

By exploring the link and searching for data related to each question, we should be able to find the answers.