Final answer:
Approximately 15% of the earth's land surface is protected.
Step-by-step explanation:
The percentage of the earth's land surface that is protected varies depending on the source and the definition of 'protected.' Generally, it is estimated that around 15% of the earth's land surface is protected. This includes national parks, nature reserves, wildlife sanctuaries, and other areas that are designated for conservation and preservation purposes. Examples of protected areas include Yellowstone National Park in the United States, Serengeti National Park in Tanzania, and the Great Barrier Reef Marine Park in Australia.
Learn more about the percentage of the earth's land surface that is protected