Define human geography.
Human geography is defined by Ratzel as the synthetic study of the relationship between human societies and the earth’s surface. Ellen C. Semple defines it as the study of the changing relationship between the unresting man and the unstable earth.
It attempts to explain the relationship between all elements of human life and the space they occur over. It studies the relationship between the physical/natural and the human worlds, the spatial distributions of human phenomena, and the social and economic differences between different parts of the world.
Explanation
The answer utilizes the specific definitions provided in the 'Human Geography Defined' section of the text, attributing them to Ratzel and Ellen C. Semple. It further elaborates on the definition using the context that describes human geography's role in studying the relationship between physical and human worlds and spatial distributions.