What is a model of the earth’s surface?

A map is a flat model of the earths surface, whereas a globe would be a more accurate model. 

Map and the globe

Explanation:

As the earth to be understood completely has to be modeled and thus based on some sort of functionality as the further development and the knowledge of geographic research can be widened.  Thus geographers have created the maps and the globe to project the image of the earth landscape on the flat piece of paper and hence create a more detailed account of the lands, oceans and the surface of the part with effects. The map is a 2 Dimensional representation of earth and the globe is a geoid a 3 Dimensional representation of the earth. The model thus used to highlight the geographic coordinates of the world. There are various types of modeled maps like the topo, hydro, geologic and other climatic maps and all are drawn to show the earth's physical physiological features and that of the ocean's trenches and the highest peaks of elevation.

Round it to the nearest tenth

The answer is the magnetosphere.