Answer to Question 1
Relative location is at the heart of a geographic axiom known as Tobler's First Law of Geography: Everything is related to everything else, but near things are more related than distant things..
Answer to Question 2
Sauer is credited with founding the landscape perspective in American geography, based on the method of studying the transformation through time of a natural landscape to a cultural landscape. Essentially, Sauer challenged us to think of what the world would look like without people and then understand what people have done to reshape the world through time.