The least abundant gas in out atmosphere is Carbon dioxide at 0.03%.
The Qin unified China, creating the first dynasty ruled by the first emperor Qin Shi Huang. Also the Qin created of the Great Wall and a Terracotta army.
Answer:
Reference maps emphasize the location of spatial phenomena, such countries, cities, rivers, etc. ... A reference map might show bank locations, while a thematic maps shows average income in an area. It's the difference between mapping places and mapping data.