This iceberg in Scoresby Sound, East Greenland, is one of many frozen sights in the country. Photograph by Frans Lanting, Nat Geo Image Collection Craters at Lake Myvatn in Iceland are among the ...

We can use a search engine close search engineA program that finds and indexes webpages on the web. to find things on the web. The search engine acts like a digital librarian. It keeps track of all ...

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