Answer to the question no. 1

Difference Between Map & Earth's Photograph:-
The big difference between a photograph and a map is that a map represents a vertical “plan” of a region, while a photograph presents a realistic image. These photographs cannot be used for information when we draw maps. A special kind of aerial photograph is used for the drawing of maps.

Answer to the question no. 2

Visual hierarchy, according to Gestalt psychology, is a pattern in the visual field wherein some elements tend to "stand out," or attract attention, more strongly than other elements, suggesting a hierarchy of importance.