Which soil is better between the soil hillside or the soil on a valley floor

As our current atmosphere formed, the concentrations of various atmospheric gases fluctuated. match each gas with the explanation that best describes how its proportion changed during the evolution of the atmosphere.

Greg goes to a high school and observes the way students talk to each other. he makes notes on the words used, the atmosphere of the school and the way the students present themselves to each other. this is an example of a( research method.

Why would it be hard to live in a city state