Answer:
The six most important characteristics of a civilization are cities, government, religion, social structure, writing, and arts and architecture.
To establishing a civilization - Cities grew on rivers and bodies of water where people could farm or fish for food. Rivers provided transportation and trade. Rivers provided rich soil and water for fields.
With the invention of the stethoscope, physicians were able to listen to the various sounds made by the heart and lungs. And began to be able to identify if patients had any diseases or ailments.